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• The catalytic depolymerization of PET waste was achieved at low temperature. • More than 90 % of DET and EG yields were obtained. • The response surface methodology was utilized to optimize reaction conditions. • The 3Ni-ZnO/Al 2 O 3 catalyst demonstrated excellent stability over five cycles. Plastic waste poses a serious threat to the global environment, with recycled polyethylene terephthalate (PET) plastic accounting for a considerable portion. The application of supercritical ethanol depolymerization technology presents an effective method for recycling PET waste. This study investigated using Ni as an additive to enhance the catalytic activity of ZnO/Al 2 O 3 catalyst for PET waste depolymerization. The effects of different catalysts, catalyst dosage, reaction temperature, and reaction time on PET waste depolymerization were studied using the single-factor controlled variable method. The results showed that the 3Ni-ZnO/Al 2 O 3 was the optimal catalyst, and under the optimal conditions with catalyst dosage of 4 %, reaction temperature of 260 °C, and reaction time of 60 min, the depolymerization efficiency of PET waste could reach 100 %, with the highest yields of diethyl terephthalate (DET) and ethylene glycol (EG) of 93.6 % and 90.2 %, respectively. Response surface methodology (RSM) was used to optimize the operating conditions to obtain the highest monomer yields. The predicted optimal parameters from RSM were as follows: reaction temperature = 262.8 °C, reaction time = 63.2 min, catalyst dosage = 3.8 wt%, with the predicted highest DET and EG yields of 95.9 % and 90.7 %, respectively. The analysis of variance (ANOVA) results for DET and EG possessed the R2 values of 0.9921 and 0.9885, respectively, with p-values < 0.0001, indicating a good fit for the models. Furthermore, after five times reuse, the 3Ni-ZnO/Al 2 O 3 catalyst still exhibited good catalytic activity and stability. In conclusion, this study offers a clean, green, and sustainable alternative to recycling plastic waste. [ABSTRACT FROM AUTHOR]

Developing low-cost, high-activity, and high-stability bifunctional catalysts is crucial for rechargeable zinc-air batteries but remains a significant challenge. Herein, inspired by the efficient catalysis of the oxygen reduction reaction (ORR) by main group metals (MGMs) based single-atom catalysts (SACs), we utilized first-principles calculations to explore the ORR and the Oxygen Evolution Reaction(OER) catalytic potential of 59 two-dimensional metal-containing covalent organic polymer supported MGMs based SACs under the constant charge method (CCM). The bader charge, the partial density of states (PDOS), p-band center (ε p) are utilized to study the origin of OER/ORR, and it is found that the charge transfer between metal atoms and nitrogen, as well as the ε p of oxygen after the adsorption reaction of oxygen-containing intermediates, are the main factors affecting catalytic activity. Then, we further used the constant potential method (CPM) and microkinetic simulation to verify the catalytic performance of the candidates screened by the CCM. Finally, we confirmed the outstanding catalytic activity and stability of (Sb)COF-Ppcfe (U 1/2 = 0.82 V, U = 1.65 V) and (Bi)COF-Ppcfe (U 1/2 = 0.86 V, U = 1.56 V) in neutral or alkaline environments. This work provides essential theoretical guidance for the design of more efficient and rational two-dimensional metal-containing covalent organic polymer catalysts. [Display omitted] • Integrating Constant Charge and Potential Methods. • The main group metal's p-orbitals dominate the catalytic activity. • Metal-N charge transfer and ε p of O in intermediates unveil catalytic origins. • Exceptional bifunctionality in (Sb)COF-Ppcfe and (Bi)COF-Ppcfe catalysts. • Catalyst activity relates to species distribution at different pH and potential. [ABSTRACT FROM AUTHOR]

Carbon-supported metal nanoparticles are indispensable catalysts to enabling catalytic water splitting technologies because of their unique size-dependent properties and strong metal-support interactions. Herein, we proposed a two-step synthesis strategy, using imine-type covalent organic frameworks (COFs) as a platform to synthesize nitrogen-doped carbon-supported Au with ultra-high specific surface area through the high-temperature pyrolysis. Thanks for the polarity of imine, the growth of Au NPs in Au x /NC are ultrafine, monodispersed, and the size of Au can be precisely controlled by adjusting the amount of the metal precursor during the carbothermal reaction. Such framework structure with numerous active sites provided by the COFs renders Au x /NC ultrahigh catalytic activity and durability for hydrogen evolution reaction (HER) in acid electrolyte. Most significantly, when illumination occurs, Au 5nm /NC catalyst presents a reduced HER overpotential from 416 mV to 43 mV and a shrunken charge-transfer resistance from 258 to 17 Ω, making the Au 5nm /NC a promising stable catalyst for the LSPR promoted hydrogen evolution reaction. • Au x /NC heterostructure was prepared via a two-step synthesis strategy. • The size of Au is highly tunable and precisely controlled. • This work highlights LSPR effect enhancement of noble metal catalyst on HER application. [ABSTRACT FROM AUTHOR]

Ammonia has recently attracted attention as a hydrogen carrier and fuel, based on the power-to-fuel concept. This concept can be realized using Ru-supported rare-earth oxides for the synthesis of ammonia from hydrogen and nitrogen (3H 2 + N 2 → 2NH 3) under mild conditions. However, at a high H/N ratio, Ru catalysts exhibit hydrogen poisoning, which reduces their activity for ammonia synthesis. This study investigates the effect of the H/N ratio on the ammonia synthesis activity of the developed Ru catalyst Ru(5 wt%)/Ce 0.5 La 0.4 Si 0.1 O 1.8 under isothermal conditions (350−500 °C). The optimal H/N ratio for achieving the highest catalytic activity decreases as the temperature is lowered (H/N = 0.5 at 350 °C; H/N = 2.0−2.5 at 450 °C). In a multibed reactor, adjusting the H/N ratio to a lower value in the downstream catalyst beds—where the temperature decreases along the gas flow path—can enhance the overall rate of ammonia production by optimizing the reaction conditions in these cooler stages. We propose a system to control the H/N ratio for each catalyst bed in a multibed reactor and demonstrate an increase in the rate of ammonia production when using a double-bed reactor containing the Ru/Ce 0.5 La 0.4 Si 0.1 O 1.8 catalyst. The proposed system offers various opportunities to accelerate the use of ammonia as a hydrogen carrier and fuel. [Display omitted] • An NH 3 synthesis system tailored to the properties of Ru catalysts is proposed. • The developed Ru catalyst is used to demonstrate the effectiveness of this system. • The H/N ratio at which the catalyst exhibits the highest activity shifts toward a lower value at lower temperatures. • A double-bed reactor that enables H/N ratio control in both beds is developed. • The total NH 3 production rate in the reactor is enhanced by H/N ratio control. [ABSTRACT FROM AUTHOR]

The development of photocatalytic materials with good adsorption capacity and high visible light activity is essential for efficient and stable photocatalytic hydrogen production from formic acid dehydrogenation. The wide band gap of TiO 2 photocatalyst materials limits their application in the field of visible light catalysis. In this work, a new composite material, Pd/CQDs/TiO 2 –NH 2 , is developed. Here, Pd is attached to amine-functionalized mesoporous titanium dioxide modified with carbon quantum dots (CQDs). This configuration is designed to enhance the catalytic activity for formic acid dehydrogenation when exposed to visible light. The Pd/CQDs-1/TiO 2 –NH 2 catalyst exhibited outstanding performance under visible light, achieving a turnover frequency (TOF) of 2666.1 h−1 at 308 K and perfect hydrogen selectivity. Compared to the Pd/TiO 2 –NH 2 catalyst with a TOF of 1715.5 h−1, this is a significant improvement. The data implies that the addition of CQDs significantly increases light efficiency, aids in the separation of photogenerated charge carriers, and enhances hydrogen production. Ultimately, the experiments clarified how the combined action of Pd, CQDs, and TiO 2 –NH 2 synergistically boosts the catalytic dehydrogenation of formic acid under visible light. The findings present an innovative approach to improving Pd/TiO 2 schottky materials. • Ultrafine Pd nanoparticles were immobilized on CQDs/TiO 2 –NH 2. • Pd/CQDs-1/TiO 2 –NH 2 catalyst showed the best photocatalytic FA dehydrogenation under full-spectrum light. • The superior photocatalytic activity is due to the introduction of CQDs and the Mott-Schottky effect. [ABSTRACT FROM AUTHOR]

The production of hydrogen from directly catalytic ammonia decomposition shows promise in improving the ammonia viability for engine use. For practical application, it is demanded to investigate additives as well as their impact mechanism on the catalytic properties of transition metal catalysts. Herein, a series of Co/CeO 2 catalysts were prepared via a facile precipitation method and the effect of Mg adding was investigated. It is found that addition of 1% Mg decreased the catalytic activity of 5% and 10% Co/CeO 2 , while increased that of 20% Co/CeO 2. Systematic characterizations revealed that Mg promoted the metal-support interaction, which not only benefited the dispersion of Co, but also increased the valence state of Co and enhanced the reducibility. Also, more oxygen vacancies were generated, thus benefiting the reaction process. This work invested new insights into the role of alkaline-earth metal in NH 3 decomposition and provided a strategy to modulate the hydrogen–ammonia ratio which is vital for NH 3 combustion. [Display omitted] • Mg addition decreased the catalytic activity of 5 % and 10 % Co/CeO 2 , while improved that of 20 % Co/CeO 2. • Mg promoted the dispersion of Co over 20 % Co/CeO 2. • Mg increased the valence state of Co and enhanced the reducibility of 20 % Co/CeO 2 via strengthening the metal-support interaction. • Mg generated more oxygen vacancies over 20 % Co/CeO 2 , which benefited the reaction. [ABSTRACT FROM AUTHOR]

Developing cost-effective and high-performance electrocatalysts is crucial for overcoming the slow oxygen evolution reaction (OER) observed in the process of water splitting. Herein, an exquisite iron-cobalt bimetallic sulfide featuring exposing more crystal faces and stronger crystallinity is manipulated via a mechanical stress strategy, which may offer additional active sites for the OER process. Particularly, the prepared Fe 0.5 Co 0.5 /SNC exhibits notable OER activity, characterized by a low overpotential of 310 mV at a current density of 10 mA cm−2 and a high current density of 131 mA/cm2 at a voltage of 1.8 V (versus RHE). Additionally, post-stability tests analysis on the material revealed a reversible oscillation of iron and cobalt valence states between 2+ and 3+, indicating the material's sensitivity to reactive oxygen species, which enhances its OER catalytic performance. The continuous adsorption and desorption of reaction intermediates with the material's matrix perpetually trigger the activation, maintaining the catalytic activity. Theoretical calculations suggest that orbital hybridization among iron, cobalt, and sulfur, along with an appropriate d-band center, enhance the electron exchange rate, facilitating the adsorption and dissociation of intermediates on the material, thereby promoting the OER process. Our findings provide new insights for the design and production of efficient, cost-effective OER electrocatalysts, contributing to the industrialization of OER catalysts. • Developed a new method combining hard template and mechanical stress for synthesis. • Crystallinity of iron-cobalt sulfide is 14.53 times higher than hydrothermal method. • Polyhedron exposes more active sites, enhancing OER activity with 310 mV overpotential. • Turnover frequency reaches 0.013 s-1, 2.6 times higher than IrO2's 0.005 s-1. • DOS and d-band center reveal the reaction mechanism of efficient catalysts. [ABSTRACT FROM AUTHOR]

Noble metal-free catalysts have recently attracted much attention towards overall electrochemical water splitting. However, poor kinetics of the reactions, involved in water splitting leads to lower hydrogen production in alkaline electrolytes. Hence, it is essential to design highly active, conductive and cost-efficient catalysts for water electrolysis. Therefore, a bifunctional electrocatalyst based on cobalt oxide (CoO) incorporated over nickel selenide (NiSe 2) supported on nickel foam (CoO/NiSe 2 /NF) was synthesized via a two-step process involving hydrothermal and electrochemical deposition methods. The synthesized material was characterized thoroughly using XRD, XPS, SEM and FE-SEM. After thorough characterization, all the synthesized materials were employed as electrocatalysts towards overall water splitting. The electrochemical studies revealed that CoO/NiSe 2 /NF has demonstrated excellent electrocatalytic activity towards overall electrochemical water splitting. The improved electrochemical activity of nano-hybrid could be attributed to heterogeneous structure, enhanced edge sites and the synergetic cooperation of CoO and NiSe 2. Finally, two electrode setups were prepared to perform overall water electrolysis in which CoO/NiSe 2 /NF need a cell potential of 2.03 V to attain 100 mA cm−2. The study proposes an approach for heterogeneous structure engineering to boost the catalytic performance of noble metal-free materials. [Display omitted] • CoO/NiSe 2 /NF nanohybrid synthesized hydrothermally and electrochemical deposition method. • All synthesized materials were utilized as bifunctional catalysts for overall water splitting. • Interface engineering of CoO and NiSe 2 significantly boosts electrocatalytic activity. • Abundant active sites were obtained by Interface engineering. • CoO/NiSe 2 /NF demonstrated higher activity and stability towards overall water splitting. [ABSTRACT FROM AUTHOR]

This research focused on the production of hydrogen (H 2) from formic acid (FA) using palladium nanoparticles, promoted by zirconium, on amine-functionalized RUB-15. The 2%Pd-0.2%ZrO 2 /RUB-15-NH 2 catalyst was produced through a hydrothermal technique and its physicochemical properties were characterized using various analyses including XRD, FTIR, BET, FE-SEM, TEM, EDS-dot mapping, CO 2 -TPD, and TGA. These nanoparticles were successfully created with a small size of 3.75 nm and appropriate dispersions. Zirconium oxide (ZrO 2) induced significant electronic effects between Pd and RUB-15-NH 2 and strong interaction between Pd–ZrO 2 nanoparticles and RUB-15-NH 2. The dehydrogenation process with sodium formate (SF) additive was carried out at three different temperatures in a double-necked balloon under FA/SF = 1:1 condition. Overall, 2%Pd-0.2%ZrO 2 /RUB-15-NH 2 exhibited satisfactory catalytic activity, 100% H 2 selectivity, no detectable CO production, and good reusability for H 2 production from FA. When SF was added to an FA aqueous solution for dehydrogenation, the total turnover frequency (TOF total) and the initial TOF (TOF initial) could reach 99.54 mol CO2+H2 mol pd −1 h−1 and 140 mol CO2+H2 mol pd −1 h−1 at 333 K, respectively. The stability test was measured in three cycles and showed great resistancy and activity during 140 min. The kinetic study was discussed and the first-order equation had a suitable result. Generally, the system's selectivity, high activity, stability, and simplicity in producing H 2 /CO 2 gas without CO production from FA were the key features of this catalyst. [Display omitted] • Amine-functionalized RUB-15 was used as a catalyst support in formic acid dehydrogenation. • 2%Pd-0.2%ZrO 2 /RUB-15-NH 2 showed high catalytic activity in formic acid dehydrogenation with TOF initial of 140 mol CO2+H2 mol pd −1 h−1. • The selectivity of hydrogen production was 100% without producing any contaminants. • Kinetic study was carried out using the linear and Arrhenius model. [ABSTRACT FROM AUTHOR]

Nickel selenide (NiSe) and carbon nanotubes (CNTs) heterojunction structure water electrolysis catalyst was prepared by vapor deposition method, constructing a heterogeneous phase interface between NiSe and CNTs. The interface effect between NiSe and CNTs enhanced further π-electron delocalization of CNTs, increasing the local electron density at the Ni sites. Subsequent ionic liquids (ILs) treatment further resolved the aggregation issues of NiSe nanoparticles and carbon nanotubes, and facilitated further π-electron delocalization at the heterojunction. The imidazolium cations acted as "connectors," tightly linking the CNTs and NiSe nanoparticles. The NiSe/CNT-IL exhibited an HER overpotential of 82 mV at 10 mA cm⁻2 in 1 M KOH. Additionally, as a full water electrolysis catalyst in a water electrolyzer, it achieved a single-cell voltage of 1.965 V at a maximum current density of 500 mA cm⁻2 at 60 °C. This direct IL functionalization for CNTs facilitates the electron transfer process and ILs can serve as the electron acceptor with superior hydrogen adsorption. • The delocalization of electrons in the carbon nanotubes is enhanced, increasing the electron density near the Ni sites. • The ionic liquid improves the dispersion of carbon nanotubes. • The ionic liquid coats the catalyst surface, stabilizing catalyst particles and enhancing catalytic activity and selectivity. • The hydrophilicity of the catalyst is improved. [ABSTRACT FROM AUTHOR]

Chemical (ion exchange resin) and biomass (water hyacinth leaves) as carbon precursors are adopted to prepare two kinds of bimetallic carbide (Fe 2 MoC)-based catalytic materials. It is found that, compared with the material that use ion-exchange resin as carbon precursor (N–Fe 2 MoC-RG), the material that use water hyacinth as carbon precursor (N–Fe 2 MoC-WHG) has more advantages in cost, environment protection, synthesis simplicity, and catalytic activity for oxygen reduction reaction (ORR). Therein, the N–Fe 2 MoC-WHG as a cathode catalyst displays a half-wave potential of 0.905 V (vs. RHE) for catalyzing ORR in alkaline media, and gets a high peak power density of 1.52 W cm−2 in alkaline electrolyte membrane fuel cell; moreover, the N–Fe 2 MoC-WHG displays higher power-density retention or growth rate at lower relative humidity, higher back pressure, higher working temperature and higher catalyst loading, compared with the N–Fe 2 MoC-RG. The N–Fe 2 MoC-WHG is one of the most active precious metal-free catalysts reported so far, and its stability is very excellent. [Display omitted] • Green process can synthesize Fe 2 MoC at lower temperatures. • Fe 2 MoC by Green process is more active in ORR than traditional process. • Green process obtained Fe 2 MoC is highly stable, costs low, and emits no pollution. [ABSTRACT FROM AUTHOR]

Designing a highly effective bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is a sensible approach for generating enormous hydrogen fuel by electrochemical water splitting. Herein, a high performance of ZIF-derived Co 3 S 4 on WS 2 -WO 3 electrocatalyst was developed for overall water splitting reactions. For developing the mixed phase of WS 2 -WO 3 , thioacetamide (TAA) played a crucial role as a sulfur source and acted as intercalating agent for expanding the layers of 1T WS 2 via the possible generation of NH 4 + ion. The high electrocatalytic performances is attained by the homogeneous incorporation and tunable properties of nano-sized Co 3 S 4 on WS 2 -WO 3. The electrocatalyst showed remarkable HER performance with an overpotential of only 73 mV and good OER efficiency with an overpotential of 307 mV at 10 mA/cm2. The long term chronopotentiometry and CV cycles performances convinces the stability of the electrocatalysts. A reasonable two-electrode overall water splitting performance was achieved by the WS 2 -WO 3 /Co 3 S 4 electrocatalyst in an asymmetric device, paving the path for more developments in the design and optimization of electrocatalysts for renewable energy conversion. [Display omitted] • A new kind of bifunctional electrocatalyst of ZIF-derived Co 3 S 4 on WS 2 -WO 3. • Ammonium ion intercalation promotes in increased 1T WS 2 layers. • Heterostructure interface between WS 2 -WO 3 and Co 3 S 4 expands catalytic activity. • WS 2 -WO 3 /Co 3 S 4 electrocatalyst provides excellence in HER activity. [ABSTRACT FROM AUTHOR]

The metastable phase molybdenum carbide-based (α-MoC 1-x) catalysts stand out as a class of the most promising representatives among the non-sulfide catalysts for the synthesis of higher alcohols (HAS) from syngas (CO/H 2) due to their noble metal-like characteristics, resistance to coking, sulfur tolerance and weak C–O bond dissociation. However, the synthesis of α-MoC 1-x commonly involves temperature-programmed ammonification and carburization (TPAC) or the consumption of noble metals. The α-MoC 1-x prepared by TPAC usually exhibited large particle size, low dispersion and poor catalytic performance. Herein, we developed a facile and continuous thermal plasma method for synthesizing nanosized α-MoC 1-x , which was highly dispersed on amorphous carbon (α-MoC 1-x /C-Pla). Compared with the α-MoC 1-x prepared by TPAC method (α-MoC 1-x -TPAC), the α-MoC 1-x /C-Pla catalyst exhibited higher CO conversion and excellent stability. The high dispersion and reactant adsorption/desorption capacity of α-MoC 1-x /C-Pla contributed to its high catalytic activity, while the anti-aggregation property of the nanosized α-MoC 1-x in α-MoC 1-x /C-Pla conferred the high stability for the α-MoC 1-x /C-Pla catalyst. [Display omitted] • A facile and continuous method for synthesizing α-MoC 1−x /C-Pla was developed. • Nanosized α-MoC 1−x particles were well dispersed on carbon in α-MoC 1−x /C-Pla. • α-MoC 1−x /C-Pla exhibited high activity and stability for syngas to higher alcohols. [ABSTRACT FROM AUTHOR]

The rapid detection and early warning of H 2 leakage at relatively low temperatures are crucial for ensuring the safety of human life and property. Tungsten trioxide (WO 3) nanocubes are promising gas-sensing materials due to their relatively large surface area, high activity, and low cost. However, the application of pure WO 3 nanocube for hydrogen (H 2) detection is limited by poor sensing properties, such as low response and high operating temperature. In this study, we synthesized WO 3 nanocubes decorated with varying amounts of platinum oxide (PtO) through an impregnation route followed by calcination. The optimized PtO-WO 3 sensor exhibited a high response value of 340 and an ultrafast response time of 1 s–100 ppm H 2 at the optimum operating temperature of 200 °C. Additionally, the sensor demonstrated a low detection limit of 123 parts per billion (ppb) for H 2 and exhibited excellent repeatability, selectivity, and long-term stability. The enhanced gas sensing performance can be attributed to the synergistic effects of the heterostructure between PtO and WO 3 , and the catalytic activity of PtO as well as platinum (Pt). The PtO-WO 3 sensor shows great potential for practical applications in detecting H 2 in air. • PtO-decorated WO 3 nanocubes were successfully prepared. • The PtO-WO 3 sensor demonstrates an ultrafast response time of 1 s towards 100 ppm H 2. • The PtO-WO 3 sensor has an experimentally determined detection limit of 500 ppb. [ABSTRACT FROM AUTHOR]

The development of bifunctional electrocatalysts with high efficiency for overall water splitting is still a challenging task. In this work, we introduce a novel one-step synthesis method for Pt/NiFe layered double hydroxide (LDH) on an iron-nickel foam (INF) substrate under mild conditions. This method eliminates the need for additional Ni or Fe ions and facilitates in-situ etching and growth processes under mild conditions, resulting in a higher active surface area, well-dispersed low-loading Pt nanoparticles, and a self-supported electrode without binders. These features collectively enhance electron transfer and catalytic activity for both HER and OER. The Pt/NiFe LDH/INF exhibits remarkable water splitting performance, requiring a cell voltage of only 1.44 V at10 mA cm−2 when used as both anode and cathode. Additionally, it remains stable at 20 mA cm−2 for at least 16 h. The exceptional water splitting activity of Pt/NiFe LDH/INF in alkaline solution can be attributed to the synergistic effects of Pt and NiFe LDH, which improve the hydrogen evolution reaction and oxygen evolution reaction efficiencies. The results provide valuable insights into designing bifunctional electrocatalysts with low Pt loading for optimal water splitting performance at low operating cost. [Display omitted] • Novel one-step synthesis of bifunctional Pt/NiFe LDH electrocatalyst under mild conditions. • Excellent bifunctional HER and OER activity of the Pt/NiFe LDH/INF catalyst. • Water splitting cell voltage of 1.44 V at 10 mA cm−2 with good stability. • Enhanced water splitting performance of the low-loading Pt with NiFe LDH. [ABSTRACT FROM AUTHOR]

Poor catalytic activity is a significant challenge that needs to be addressed to enable the effective use of perovskite electrodes in symmetrical solid oxide cell (SOC). In this study, high-activity Ni ions were doped into the La 0.3 Sr 0.7 Fe 0.9 Ti 0.1 O 3-δ (LSFTi91) perovskite lattice, which endowed the materials with different facilitation effects in different atmospheres. In an oxidizing atmosphere, the introduction of Ni ions enables La 0.3 Sr 0.7 Fe 0.8 Ti 0.1 Ni 0.1 O 3-δ (LSFTNi811) to exhibit higher conductivity and oxygen vacancy content, which enhances the adsorption and dissociation of gases. When used as symmetrical electrodes in a solid oxide electrolysis cell, the LSFTNi811 symmetric cell presents higher electrolysis performance than LSFTi91 (1.78 A cm−2 vs. 1.57 A cm−2) at 1.5 V and 800 °C. This is the highest level reported for a single-phase perovskite electrode, underlining its excellent catalytic activity. In a reducing atmosphere, although Ni doping weakens the structural stability of the material, a large number of NiFe nanoparticles precipitate the H 2 reaction after material decomposition. In this situation, LSFTNi811 achieves better performance than LSFTi91 as a symmetrical electrode for the solid oxide fuel cell both before and after decomposition. Therefore, LSFTNi811 is a promising symmetrical electrode material for SOCs. [Display omitted] [ABSTRACT FROM AUTHOR]

Piezo-photocatalysis materials that can combine the piezoelectric effect in photocatalytic processes are very attractive for promising applications in water splitting and contaminant degradation. The perovskite oxides with adjustable exposed crystal facets are expected to optimize the catalysis activities by exposing the high-energy planes. In this work, we develop a salt-assisted strategy that controllably prepares anisotropic SrTiO 3 particles with a large number of surface defects, which exhibit good piezo-photocatalytic features. The exposure of the crystal facets can be tuned by changing the assistants (NaCl or SrCl 2). The SrCl 2 can lead to the exposure of the (110) plane in one-dimensional SrTiO 3 particles and NaCl can induce the cubic SrTiO 3 particles with the exposure plane of (200). Attributed to the exposed high-energy facets and abundant oxygen vacancies, the latter show higher activities than the former in both water splitting and dye degradation under light irradiation and ultrasonic vibration. Our work provides an approach to optimize piezo-photocatalytic activities by tuning the exposed crystal facets. [ABSTRACT FROM AUTHOR]

The design of efficient ammonia cracking catalysts is the key to developing ammonia as a hydrogen storage carrier. This paper investigated the role of Co–Al hydrotalcite carriers in ruthenium-based catalysts. Ru/Co–Al catalysts were prepared by mechanical milling, impregnation, and co-precipitation, and the catalytic activity and physicochemical properties of the catalysts were investigated, respectively. The catalysts prepared by the co-precipitation method exhibit the maximum specific surface area and metal dispersion due to the layered structure of LDH and the homogeneity of the co-precipitation method. In this study, it is concluded that the substitution of Ru during the co-precipitation preparation builds up strong metal-carrier interactions and generates a large number of oxygen vacancies. The catalyst prepared by the co-precipitation method exhibited a high H 2 generation rate (19.5 mmol·gcat−1·min−1) at GHSV = 30,000 ml·gcat−1·h−1 and 450 °C, and the performance remained stable after 50 h of reaction. This work provides a new idea for designing efficient Ru-based catalysts. We investigated the effects of different preparation routes on the ammonia cracking performance of layered structure catalysts. Among them, the Ru/Co–Al-LDOs-CP catalyst prepared by the co-precipitation one-step synthesis method shows the best catalytic performance. [Display omitted] • The CP catalyst has a maximum specific surface area and dispersion. • Substitution of Ru occurs during co-precipitation preparations. • The CP catalyst shows a high ammonia cracking conversion of 98.57 % at 500 °C. [ABSTRACT FROM AUTHOR]

Switching from the urea oxidation reaction (UOR) to the oxygen evolution reaction (OER) is a beneficial way to lower the amount of energy needed to make hydrogen gas during the hydrogen evolution reaction (HER). Due to the sluggish reaction kinetics of the six electrons reaction of UOR, designing a privileged bifunctional electrocatalyst for both HER and UOR necessitates. The 2D nano-sized non-noble metal electrocatalysts make it possible to speed up reactions and improve their electrocatalytic performance. We synthesized nickel-cobalt-MXene composite nanosheets (NiCoMXene) on the surface of copper foam using a one-pot, simple, and ultra-fast electrochemical method. This 2D electrocatalyst demonstrates high electrocatalytic performance towards HER (overpotential of 76 mV at −10 mA cm−2) with excellent durability in alkaline media. Furthermore, NiCoMXene nanocomposite served as a bifunctional electrocatalyst to investigate hydrogen gas production by a hybrid system HER coupled with UOR in seawater. The NiCoMXene requires a low overpotential for HER (81 mV) and UOR (1.38 V) to achieve a current density of 10 mA cm−2 in seawater, and the needed cell voltage to reach the same current density is 1.42 V in seawater. Our DFT analysis found a significant synergy between MXene and NiCo in the electrocatalyst. PDOS analysis showed remarkably that introducing Ni atoms to MXene shifts the d-band center to the left (lower energy), while Co atoms shifts it to the right (higher energy) and increased states near the Fermi level. This electronic structure makes the nanocomposite an ideal electrocatalyst, with MXene providing electrons and Co atoms serving as active sites for both HER and UOR. This research work can provide a useful directive to explore the electrocatalysts with outstanding catalytic activity. [Display omitted] • Synthesized a 2D NiCoMXene nanocomposite electrocatalyst with high performance for both HER and UOR. • Employed a one-pot, simple, and ultra-fast electrochemical method to synthesize NiCoMXene on copper foam. • High catalytic activity was analyzed using electrochemical techniques and density functional theory. • NiCoMXene exhibited exceptional stability, efficiency, and catalytic kinetics. [ABSTRACT FROM AUTHOR]

Solid oxide electrolysis cells (SOECs) with perovskite structures as cathodes have the potential to efficiently convert CO 2 into CO at a low cost and with high reaction kinetics. However, its catalytic activity has impeded its further progress. Enhancing SOEC performance necessitates the development of highly active cathodes. The incorporation of metal nanoparticles is a widely accepted strategy for optimizing the cathode performance. In this study, an in situ exsolution method was used to intercalate FeTe nanoparticles on a Sr 2 Fe 1.5 Mo 0.5 O 6-δ (SFMT) double-perovskite substrate (FeTe@SFMT) to effectively catalyze the CO 2 electrocatalytic reduction (CO 2 ER) in SOECs. The alloy nanoparticles formed strong interactions with the substrate, preventing agglomeration and deactivation during the reaction and thus maintaining stable active sites. An SOEC with composite perovskites as the cathode and La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3−δ (LSGM) electrolyte exhibited outstanding electrochemical performance for CO 2 electrolysis. At 850 °C and 1.8 V, the current density reached 0.53 A cm−2, producing CO at 5.37 mL min−1 cm−2 with a Faradaic efficiency of 95.6%. This study provides an innovative approach for optimizing the microstructure of SOEC electrodes and for designing efficient electrocatalysts for CO 2 electrolysis. • SOEC doped with Fe and Te in double perovskite obtained excellent CO 2 electrolysis. • FeTe alloy nanoparticles at interfaces contributed to enhance performance of SOEC. • The performance of SOEC maintained after 100 h operation. [ABSTRACT FROM AUTHOR]

To develop a low cost and high-efficiency electrocatalyst is important for the preparation of high-purity hydrogen. Herein, a series of Ir@Ni-MOF-x/NF materials (x = 0.06, 0.08, 0.09, 0.10) were obtained by anchoring iridium (Ir) nanoparticles on nickel metal-organic framework via in-situ growth on nickel foam (NF). Compared with Ni-MOF/NF, Ir@Ni-MOF-x/NF electrodes exhibit preferable hydrogen/oxygen evolution reaction (HER/OER) performance in alkaline solution. Among them, Ir@Ni-MOF-0.08/NF electrocatalyst with the optimal Ir content of ∼1.65 wt% exhibits the most excellent HER and OER activities. For HER, it exhibits a low overpotential (η 100 = 105 mV) with a small Tafel slope (21.95 mV dec−1). For OER, its overpotential is 293 mV at 100 mA cm−2 with a Tafel slope of 62.27 mV dec−1. The overpotentials are significant superior compared with the traditional Pt/C (η 100 = 218 mV for HER) and RuO 2 (η 100 = 317 mV for OER). Moreover, Ir@Ni-MOF-0.08/NF||Ir@Ni-MOF-0.08/NF couple electrode can operate at 50 mA cm−2 with 1.666 V keeping 32 h, which is more excellent than the commercial RuO 2 –Pt/C-based electrolyser. This result indicates that the introduction of Ir nanoparticles in Ni-MOF can effectively improve the catalytic activity and the Ir@Ni-MOF-0.08/NF is a potential bifunctional electrocatalyst for HER and OER. A series of iridium (Ir) nanoparticles anchored nickel metal-organic framework (Ir@Ni-MOF-x/NF) were constructed that exhibited preferable HER and OER activities. [Display omitted] • Ir@Ni-MOF-x/NF were constructed by in situ grown on nickel foam (NF). • Ir@Ni-MOF-x/NF exhibit more perfect HER and OER performance than Ni-MOF-x/NF. • Ir@Ni-MOF-0.08/NF possesses the highest electrocatalytic performance. • Ir@Ni-MOF-0.08/NF exhibits higher electrocatalytic activity than Pt/C and RuO 2. [ABSTRACT FROM AUTHOR]

Z-scheme photocatalysts for solar-driven overall water splitting have attracted tremendous attention due to their strong redox abilities and enhanced solar-light absorptions. This study focuses on the theoretical design of XAu 2 Y (X, Y S, Se, Te) heterostructures for solar-driven photocatalytic water splitting based on first-principles calculations. The band edges and internal electric fields indicate that SAu 2 S/TeAu 2 Te, SeAu 2 Se/TeAu 2 Te, TeAu 2 Te/SAu 2 Se and TeAu 2 Te/SeAu 2 S are highly efficient Z-scheme photocatalysts for solar-driven overall water splitting, with enhanced optical absorbances by 1.5–2 times and high solar-to-hydrogen energy conversion efficiencies of 20.47%, 19.94%, 16.50% and 22.81%. Furthermore, taking TeAu 2 Te/SeAu 2 S as an example, HER (Δ G H * = 0.16 e V) and OER (U = 2.25 V) reactions show excellent photocatalytic performances. These results extend the scope of solar-driven overall-water-splitting photocatalysts to group-11 chalcogenides heterostructures, which is expected to inspire the experimental fabrications and relative investigations. Z-scheme heterostructures based on XAu 2 Y (X, Y S, Se, Te) are theoretically screened for solar-driven overall water splitting, which exhibit enhanced optical absorbances, high solar-to-hydrogen energy conversion efficiencies and excellent redox reactions. [Display omitted] • The Z-scheme heterostructures are designed to effectively separate photogenerated carriers. • Constructing heterostructures promote the excellent optical absorbances. • The Z-scheme heterostructures possess high solar-to-hydrogen energy conversion efficiencies. • High catalytic activities for HER and OER are confirmed by the Gibbs free energies. [ABSTRACT FROM AUTHOR]

Catalytic methane cracking produces pure H 2 and high value-added carbon, a potentially environmentally friendly process for hydrogen production, but challenges remain in the designing of high-performance catalysts. NiVAl catalysts were obtained by reducing the hydrotalcite precursor, and the samples were analyzed by XRD, ICP, N 2 adsorption-desorption, SEM, XPS, and the impacts of reaction temperature and V/Ni ratio on the production of H 2 by cracking methane were studied. The results showed that the V doping could promote the reduction of Ni species, improve the specific surface area of the catalyst and inhibit the sintering of Ni particles. The methane cracking hydrogen yield curve illustrates that the performance of NiVAl catalyst shows a volcanic relationship with the V/Ni ratio. The Ni 2.4 V 0.6 Al catalyst exhibits optimal performance, with a stable hydrogen yield of about 80% for 210 min at 700 °C. In addition, the reaction temperature also significantly affects the catalyst performance, with high temperatures favoring increased catalytic activity and low temperatures tending to improve stability. The Ni 2.4 V 0.6 Al catalyst was reacted at 600 °C for 300 min with 68% hydrogen yield without deactivation. • NiVAl catalyst for the cracking of methane to H 2 by reduction of hydrotalcite precursors. • The effects of V/Ni molar ratios and reaction temperature on the H 2 yield were investigated. • The Ni 2.4 V 0.6 Al catalyst was stabilized for 210 min at near 80% H 2 yield at 700 °C. • NiVAl catalyst exhibits good resistance to sintering under the reaction condition. [ABSTRACT FROM AUTHOR]

Due to low content of precious metals and good stability, Ruddlesden-Popper (R–P) structure oxides are considered as promising hydrogen evolution reaction (HER) catalysts. However, related research is scarce, hindering its further improvement. In this paper, effects of strain, pH, oxygen-deficient and layer numbers on HER catalytic performance of R–P structure oxides Sr 2 RuO 4 , Sr 3 Ru 2 O 7 and Sr 3 Ru 2 O 6 were comprehensively calculated for the first time. Our results confirm that oxygen-deficient R–P Sr 3 Ru 2 O 6 is beneficial for its catalytic performance in alkaline environments. Ranking of catalytic performance in acidic environments: Sr 2 RuO 4 >Sr 3 Ru 2 O 6 >Sr 3 Ru 2 O 7 , relatively in alkaline environments: Sr 3 Ru 2 O 6 >Sr 3 Ru 2 O 7 >Sr 2 RuO 4 , which means pH actually affects the performance of R–P structure catalysts. In other words, acidic environments are conducive to the catalytic activity of Sr 2 RuO 4 , while alkaline environments are beneficial for Sr 3 Ru 2 O 6 and Sr 3 Ru 2 O 7. We also calculated the effects of tensile and compressive strains and found that 1% and 3% tensile strain can further enhance the HER catalytic performance of Sr 3 Ru 2 O 6. Taking into account various practical factors, our work investigated the HER catalytic mechanism of R–P oxides, providing theoretical guidance for the development of R–P structure catalysts. • Firstly calculated HER catalytic activity of R–P structure Sr 3 Ru 2 O 6 and Sr 3 Ru 2 O 7. • Oxygen-deficient of Sr 3 Ru 2 O 6 benefices the catalytic performance in alkaline solution. • Catalysis in acid: Sr 2 RuO 4 >Sr 3 Ru 2 O 6 >Sr 3 Ru 2 O 7 , alkaline: Sr 3 Ru 2 O 6 >Sr 3 Ru 2 O 7 >Sr 2 RuO 4. • Conducive to catalysis: acidity for Sr 2 RuO 4 , alkalinity for Sr 3 Ru 2 O 6 & Sr 3 Ru 2 O 7. • 1% & 3% tensile strain can further enhance the HER catalytic performance of Sr 3 Ru 2 O 6. [ABSTRACT FROM AUTHOR]

Integrating and advancing renewable energy storage and conversion technologies such as water splitting and rechargeable air-based batteries face significant challenges in finding appropriate catalysts that offer both high activity and low cost. This paper successfully designed efficient, cost-effective, and eco-friendly catalysts that meet the requirements for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) catalytic activity by employing two-dimensional (2D) transition metal dichalcogenides (TMDs) interface engineering combined with a single-atom doping strategy. First, the heterostructure was constructed, and its optimal layer spacing (3.13 Å) was determined by calculating the most negative binding energy. These materials were theoretically evaluated using density functional theory (DFT), demonstrating that transition metal (TM) can all be firmly attached to the S1 site of the WS 2 /ReSe 2 Z-scheme heterostructure with favorable binding energies and excellent electronic properties. By comparing the catalysts doped with different metals (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn), the three functional catalysts with the best performance were finally selected: Mn@WS 2 /ReSe 2 , Ni@WS 2 /ReSe 2, and Cu@WS 2 /ReSe 2. In particular, Mn@WS 2 /ReSe 2 exhibited exceptional promise as multifunctional catalysts, with overpotentials for the HER/OER/ORR of 0.05/0.29/0.35 V, respectively. The superior catalytic performance of this WS2/ReSe 2 Z-scheme heterostructure was attributed to the introduction of TM atoms and the synergistic interaction between rhenium and the TM atoms. This interaction facilitated more efficient electron transfer between the catalyst and the reactants, enhancing the overall catalytic activity. This research is a successful attempt to combine interface engineering with single-atom catalysis (SACs). It provided valuable insights into the design of next-generation multifunctional electrocatalysts, offering a novel approach to address the growing energy demands in an environmentally benign and economically viable way. • The catalytic performance of single atoms on WS 2 /ReSe 2 heterostructure was calculated by first principles for the first time. • Mn@WS 2 /ReSe 2 can be used as a admirable multifunctional catalyst with overpotentials for the HER/OER/ORR of 0.05/0.29/0.35 V. • Through a variety of stability tests, the latest configuration of a multifunctional catalyst was ultimately obtained. • The work function can be used as an important descriptor for multifunctional catalysts. [ABSTRACT FROM AUTHOR]

Metal-organic framework (MOF)-based electrocatalysts often undergo structural distortion during the oxygen evolution reaction (OER), which can affect their original structure and stability, and poses challenges for theoretical analysis and mechanistic exploration. Herein, vanadium (V) was doped to construct a V–Ni MOF/NF (1.0: 10) that combines structural stability with excellent catalytic activity. The introduction of V significantly suppressed the structural distortion tendency of Ni MOF during the OER process. Additionally, V doping promoted charge redistribution, which enhanced the overall oxidation state of Ni sites and increased oxygen vacancies, providing more active sites and faster electron transport capabilities, boosting the intrinsic activity. As a result, V–Ni MOF/NF (1.0: 10) can be used as a "real catalyst" directly in alkaline OER testing and further applied to seawater splitting and Zinc-air batteries. This work is the first to propose an inhibition strategy for structural distortion of MOF-based OER catalyst, offering new insights into the development of high-activity and stable MOF-based "real catalysts". The V doping significantly inhibited the structural distortion of Ni MOF during the OER process, imparting excellent structural stability of Ni MOF and allowing it to be directly used as a "real catalyst" in electrocatalytic applications. [Display omitted] • V doping inhibited Ni MOF structural distortion during OER. • The first time to study the inhibition strategy of MOF-based OER catalyst distortion. • V–Ni MOF/NF (1.0: 10) showed superior OER activity and excellent structural stability. • V–Ni MOF/NF (1.0:10) excelled in seawater splitting devices and Zinc-air batteries. [ABSTRACT FROM AUTHOR]

Electrocatalytic NO reduction reaction (NORR) to synthesize ammonia is of great scientific significance and application value to solve both NO removal and ammonia synthesis. However, the catalytic activity and selectivity are suppressed by the inherent linear scaling relations between the adsorption energies of NORR intermediates. In this work, we have systematically investigated the catalytic performance of specific confined M 2 CO 2 (M = Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W) MXenes for electrochemical reduction of nitric oxide to ammonia. Our results show that the bowl-like confined structure in MXenes can effectively catalyze NORR under the optimal reaction pathway of ∗NO→∗NOH→∗N→∗NH→∗NH 2 →∗NH 3. In particular, the NORR on V 2 CO 2 and Cr 2 CO 2 MXenes are thermodynamically spontaneous (U L = 0 V), which are superior to those of most reported NORR electrocatalysts. Then, we highlight that modifying the transition metal elements in MXenes can selectively tune the adsorption energies of ∗NH 2 and ∗NH 3 , thus breaking their linear scaling relations towards the lower overpotential of NORR. Further analysis of the d-band center and work function illuminates that the modulation mechanism originates from the tunable electronic properties and electron transfer ability of M 2 CO 2 MXenes. Furthermore, the specific confined structures can effectively inhibit the formation of H 2 , N 2 , or N 2 O, which confers V 2 CO 2 and Cr 2 CO 2 MXenes with excellent NH 3 selectivity. This work not only pioneers the effect of specific confined structures on the catalytic performance of MXenes, but also provides general design principles for glorious-performance NORR electrocatalysts. [Display omitted] • Selective reduction from NO to NH 3 can be realized on O-vacancy M 2 CO 2 MXene. • O-vacancy M 2 CO 2 MXene possess superior electrocatalytic performance of NORR. • Design principles to break scaling relations in nitric oxide reduction were proposed. • The novel strategy will accelerate the practical applications of MXenes on catalysis. [ABSTRACT FROM AUTHOR]

Developing efficient bifunctional electrocatalysts is crucial for advancing the practical application of electrocatalytic water splitting. Cobalt phosphide (CoP) shows great potential for overall water splitting but the weak oxygen evolution reaction (OER) catalytic activity hinders its development. Herein, urchin-like CoP/FeP@NF-1 was designed and fabricated on nickel foam via the hydrothermal and phosphorization to improve the OER performance and achieve efficient overall water splitting. The formation of CoP/FeP heterogeneous phases was successfully modulated the local electronic structure of CoP and increased the content of Co3+ species to enhance the catalytic activity of OER. Moreover, the urchin-like morphology and hydrophilic surface of CoP/FeP@NF-1 not only exposed more active sites but also promoted the transfer of electrolyte and products. So, CoP/FeP@NF-1 only required overpotentials of 67/153 mV for HER and 235/285 mV for OER to achieve the current density of 10/100 mA cm−2, respectively. Meanwhile, the assembled electrolyzer with CoP/FeP@NF-1 as the cathode and anode presented a cell voltage of 1.56 V to achieve 10 mA cm−2. In situ Raman characterization suggested that the formed oxyhydroxides during the OER process were the active phases. Furthermore, theoretical calculations revealed that the doped Fe accelerated HER by promoting the water dissociation and was also the main active site of OER. This work provided insights into the synthesis of efficient CoP-based bifunctional electrocatalysts for overall alkaline water splitting. Urchin-like CoP/FeP@NF-1 electrocatalyst with the hydrophilic surface and high Co3+ content was designed through doping engineering strategy. CoP/FeP@NF-1 showed high OER and HER catalytic activities due to its abundant exposed active sites, accelerated reaction kinetics and improved charge/mass transfer abilities. [Display omitted] • Urchin-like CoP/FeP@NF-1 with hydrophilic surface exposed more active sites and promoted mass transfer. • CoP/FeP@NF-1 with optimal local electronic structure and high Co3+ content showed high OER activity. • CoP/FeP@NF-1 exhibited excellent electrocatalytic performance for HER, OER and overall water splitting. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Colorimetric qualitative and sensitive quantitative detection of Salmonella Typhimurium holds significant importance for ensuring food safety and preventing foodborne illnesses. In this study, an ultra-high catalytic activity and biocompatible nickel-platinum nanoparticle (NiPt NP) nanozyme is successful synthesized to prepare a nanozyme-linked immunosorbent assay (NLISA) strategy for the detection of Salmonella Typhimurium. The synthesized NiPt NP exhibit high oxidase-like catalytic efficiency, with a Michaelis-Menten constant of 0.493 m M , similar to that of natural horseradish peroxidase (HRP). The maximal reaction velocity was determined to be 1.97 × 10−7 M ·s−1, 1.97-fold higher than that of the HRP (1.0 × 10−7 M ·s−1). Meanwhile, the antibody employed in this NiPt NP-based NLISA exhibits exceptional capture efficacy, generating a stable immune complex with Salmonella Typhimurium. The NiPt NP-based NLISA demonstrates sensitivity, specificity, convenience, and cost-efficiency for the detection of Salmonella Typhimurium. Under optimal conditions, this NiPt NP-based NLISA demonstrates a quantitative range of 103∼106 cfu/mL with a detection limit as low as 103 cfu/mL. A single-blind experimental testing detects different concentrations of Salmonella Typhimurium-spiked skim milk, indicating the application potential of the proposed NLISA in real samples. In all, this research provides novel insights into the synthesis of nanozymes with excellent catalytic activity and their applications in Salmonella Typhimurium biosensing. [ABSTRACT FROM AUTHOR]

Hyaluronic acid (HA) is widely used in food and pharmaceutical industries. As a UDP-glucose dehydrogenase, hasB catalyzes the conversion of UDP-Glc to UDP-GlcUA in HA biosynthesis. However, little is known about structural characteristic and enzymatic property of hasB. Owing to high-yield HA production by Streptococcus zooepidemicus CR003, an in-depth analysis of hasB from CR003 was investigated in this work. HasB contains 401 amino acids with a molecular weight of 44.96 kDa, which exhibited 62.69 % homology with that from S. pyogenes. The optimal reaction condition for the purified hasB by heterologous expression was 30 °C and pH 9.0. Cu2+ and Zn2+ significantly inhibited hasB activity, whereas Mg2+ had a stimulatory effect. K m values of hasB for UDP-Glc and NAD+ were 0.1378 and 0.7583 mM, and V max were 391.3 and 548.8 μmol/min/mg, respectively. To our knowledge, it is currently the highest reported enzyme catalytic activity of hasB. Molecular docking showed that the binding energies of hasB with UDP-Glc and NAD+ were −731.01 and −314.17 kcal/mol, respectively, and the interaction forces between hasB and the substrate play a crucial role in stabilizing the conformation of protein-substrate complexes. Conclusively, hasB from CR003 showed high catalytic efficiency, which has great application potential for HA production. [Display omitted] • An in-depth analysis of hasB from S. zooepidemicus CR003 was investigated. • K m and V max values of hasB for UDP-Glc were 0.1378 mM and 391.3 μmol/min/mg, respectively. • Cu2+ and Zn2+ significantly inhibited hasB activity, whereas Mg2+ had a stimulatory effect. • It is currently the highest reported enzyme catalytic activity of hasB from S. zooepidemicus. [ABSTRACT FROM AUTHOR]

CO 2 serves as a crucial precursor for synthesizing aromatic, offering a resultful pathway for utilizing non-petroleum carbon sources. Nonetheless, the Anderson-Schulze-Flory (ASF) distribution limits aromatics selectivity, challenging the direct conversion of CO 2 into specific aromatic products. Bifunctional catalysts consisting of ZnCr 2 O 4 , ZnAl 2 O 4 and ZnIn 2 O 4 spinel with nano-flake ZSM-11 zeolite were constructed and investigated for converting CO 2 to valuable aromatics. Remarkably, the selectivity towards aromatics greatly surpasses the constraints of ASF. Under identical reaction conditions, the single pass CO 2 conversion of the ZnCr 2 O 4 /ZSM-11 increased by 7.2% and 5.2%, while the aromatic selectivity rose by 9.5% and 10.5%, respectively, compared to the ZnAl 2 O 4 /ZSM-11 and ZnIn 2 O 4 /ZSM-11. Additionally, under optimal conditions (300 °C, 3.5 MPa and a gas hourly space velocity (GHSV) of 1800 mL·g cat −1·h−1), ZnCr 2 O 4 /ZSM-11 displayed outstanding aromatic selectivity of 90.5% (without CO) alongside a single pass CO 2 conversion of 23.6%. Simultaneously, the synthetic ZSM-11 facilitates the timely diffusion of monocyclic aromatics and the production of C 8 –C 12 monocyclic aromatics, which constitute 97.2% of the total aromatic products, while polycyclic aromatics account for only 0.2%. Even after 100 h, the ZnCr 2 O 4 /ZSM-11 catalyst maintained its significant catalytic activity with CO 2 conversion and aromatic selectivity at 22.0% and 88.0%, respectively. These results highlight the potential of ZnCr 2 O 4 /ZSM-11 for directly converting CO 2 to valuable aromatics. [Display omitted] • ZnX 2 O 4 (X = Cr, In, Al) spinels were designed to compare the catalytic properties. • ZnCr 2 O 4 /ZSM-11 bifunctional catalyst enables direct CO 2 to aromatics conversion. • ZnCr 2 O 4 /ZSM-11 achieved 90.5% aromatics selectivity, 23.6% CO 2 conversion. • Remarkably, C 8 –C 12 monocyclic aromatics constitute 97.2% of the total aromatic. • Post 100 h, catalyst still gave 22.0% CO 2 conversion, 88.0% aromatics selectivity. [ABSTRACT FROM AUTHOR]

Proton-conducting solid oxide fuel cells (H–SOFCs) are promising devices for efficient chemical-to-electrical energy conversion at low temperatures. Extensive research has focused on enhancing the catalytic activity of cathodes. In this study, we employ a Sn doping strategy to modify the Ruddlesden-Popper structured La 2 NiO 4+δ (LNO) cathode. Experimental results demonstrate that Sn doping significantly improve the oxygen reduction reaction (ORR) activity and protonation capability of the cathode. First-principles calculations further reveal that the La 2 Ni 1-x Sn x O 4+δ (LNSOx) cathode exhibits a lower oxygen vacancy formation energy compared to bare LNO. The peak power density of H–SOFCs with Sn-doped LNO reaches 1563 mW cm−2 at 700 °C, notably higher than previously reported LNO-based H–SOFCs. These findings confirm the potential of Sn-doped LNO as an effective cathode material for H–SOFCs. • Sn Doping significantly improve the oxygen reduction reaction (ORR) activity. • A peak power density of 1563 mW cm−2 is reached at at 700 °C. • Sn Doping effectively reduces the extent of CO 2 chemical adsorption. [ABSTRACT FROM AUTHOR]

Furfuryl alcohol (FA) is an important chemical and has extensive applications in varied fields. To realize the highly selective hydrogenation of furfural (FF) to produce FA, the key is the preparation of the catalysts with excellent performance. Herein, a very simple wet chemical method is developed for the one-step preparation of PdAg nanosponges (NSs). Specifically, with Pd(OAc) 2 and AgNO 3 as precursors, and ethylene glycol (EG) as both solvent and reducing agent, PdAg NSs can be grown and assembled at mild temperature of 40 °C. Throughout the reaction, no any surfactants and additional reducing agents are applied. The as-prepared PdAg NSs possess 3D self-supported alloy structures, "clean" surface, abundant pores, high specific surface area and rich defects. In the FF hydrogenation reaction at 60 °C under 1.5 MPa H 2 pressure in the mixed solvent of ethanol and water (1 : 4 in volume ratio), the self-supported PdAg-1 NSs (1 : 1 in Pd/Ag molar ratio) exhibit superior catalytic performance than other PdAg NSs, pure Pd sample and commercial Pd/C (10%). With PdAg-1 NSs as catalyst in the absence of support, 100% FF can be converted and the selectivity toward FA is as high as 97.1% at 36.0 h of reaction. After 4 cycles, PdAg-1 NSs still maintain the high catalytic activity in FF hydrogenation and high selectivity toward FA, which may originate from the 3D self-supported structures, high specific surface area, "clean" surface, rich defects and electronic synergistic effect between Pd and Ag. This simple fabrication of PdAg NSs introduces new ideas for the synthesis of other nanostructured bi- and multi-metallic catalysts for highly selective FF hydrogenation to FA and other advanced applications. The defect-rich PdAg nanosponges are one-step synthesized in ethylene glycol at 40 °C without the uses of any surfactants, additional reducing agents and supports, and exhibit highly catalytic activity and selectivity for furfural hydrogenation to produce furfuryl alcohol under mild conditions. [Display omitted] • PdAg nanosponges (NSs) were one-step grown in ethylene glycol at 40 °C. • The synthesis was achieved without any seed, surfactant and additional reductant. • The PdAg NSs have rich defects and self-supported structures. • PdAg NSs has excellent catalytic performance for furfural (FF) hydrogenation. • 100.0% conversion of FF and 97.1% selectivity to furfuryl alcohol can be achieved. [ABSTRACT FROM AUTHOR]

The current emphasis of research on PEM fuel cells is the exploration of novel, resilient, and very efficient electrocatalysts that do not rely on platinum, while also ensuring long-term stability. This study aimed to enhance the catalytic activity as cathode electrocatalysts by synthesizing Palladium-cobalt alloy nanoparticles using the ultrasonic spraying (US) technique and then dispersing them over a carbon black substrate. The ultrasonic spray method produces crystalline catalysts in the liquid-vapor interface reaction without requiring additional energy. Analyses were performed using XRD, SEM, EDS, XPS and TEM to determine the structural and morphological properties of the nanocatalysts. XRD analysis determined the average particle size of USCo–Pd/C and US-CoPd/C nanocatalysts to 1.37 nm and 1.09 nm, respectively. CV measurements identified ECSA values for USCo–Pd/C and US-CoPd/C as 7.1 m2/g Pd and 8.9 m2/g Pd. The relative performance ranking of cathode electrocatalysts for PEM fuel cells was evaluated at a cell temperature of 70 °C. The order of reactivity for the catalysts is as follows: US-CoPd/C > USCo–Pd/C > PdCo/C > Pd/C. The better electrochemical performance of USCo–Pd/C and US-CoPd/C nanocatalysts as cathode catalysts in PEM fuel cell applications, in comparison to Pd/C and PdCo/C catalysts, can be attributed to the modification of the electronic structure of palladium. This modification depends on the synthesis of cobalt and palladium metals together using the US method and the synergistic effect of the catalysts. [Display omitted] • CoPd nanocatalysts were synthesized via ultrasonic spray at gas-liquid interfaces. • US-CoPd/C showed 3–3.5x higher activity than PdCoC synthesized by reduction. • PEM fuel cell performance improved with increasing cell temperature. • Ultrasonic spray synthesis maintained activity, unlike conventional methods. [ABSTRACT FROM AUTHOR]

The undesirable intrinsic activity of tungsten oxides derived from poor conductivity and adverse hydrogen absorption energy is insufficient for their practical application. Herein, the tungsten oxides with adjustable oxygen vacancies were synthesized by a facile pyrolysis of ammonium paratungstate hydrate in controllable atmospheres. The structural characterizations confirmed that oxygen vacancies and crystalline phases in tungsten oxides depend on the pyrolysis atmosphere. The electrochemical test indicated a strong dependence between catalytic activity and oxygen vacancies in tungsten oxides. Combining experimental results and density functional theory calculations verified that introducing oxygen vacancies into tungsten oxides effectively modulates the surface electronic structure. The enhanced electronic conductivity by reducing band gap accelerates the electron transfer from catalysts into the reactive species. The optimized hydrogen adsorption energy by electron migration from O into W promotes the activation of reactive species at W sites and the desorption from O sites, thereby accelerating the reaction kinetics. The regulated oxygen vacancies in tungsten oxides was availably achieved by controlling the annealing atmospheres for ammonium paratungstate hydrate. The as-prepared tungsten oxide catalysts exhibit a strong dependence between oxygen vacancies contents and catalytic activity for hydrogen evolution reaction. The experimental observations and theoretical calculations confirm that oxygen vacancies introduced into tungsten oxides can enhance the electronic conductivity and optimize the hydrogen adsorption energy to remarkably improve the catalytic activity. [Display omitted] • Oxygen vacancies in WO 3 were regulated by controlling annealing atmospheres. • WO 3 exhibits a strong dependence between oxygen vacancies and catalytic activity. • Introducing oxygen vacancies reduces band gap to improve electronic conductivity. • Oxygen vacancies optimize hydrogen adsorption energy on tungsten oxides. [ABSTRACT FROM AUTHOR]

The LiNi 0.8 0 Co 0.15 Al 0.05 O 2-δ (LNCA) electrode exhibits better catalytic activity in low-temperature solid oxide fuel cells (LT-SOFCs). However, LNCA still faces some challenges in commercialization due to poor stability, scarcity of lithium resources, and high costs. Here, Na-doped LNCA electrode not only enriches oxygen vacancies and prolongs long-term stability, but also maintains a layered structure and reduces costs. At 550 °C, under the optimal ratio of L 0.85 Na 0.15 NCA electrode, the maximum power density (MPD) of a single cell reaches 1147 mW cm−2 with an open circuit voltage (OCV) of 1.13 V and a polarization impedance (R p) of 0.21 Ω cm2, which is 30.6% higher than the single cell power (878 mW cm−2) of the Na-undoped LNCA electrode. The cell maintained long-term stability for 108 h at a constant current density of 156.25 mA cm−2 and a voltage of about 0.9 V. The results indicate that Na-doped LNCA is an effective strategy to improve the electrochemical performance of LNCA and long-term stability of cell. [Display omitted] • The crystal structure of Na-doped NCAL electrode is more stable. • The L 0.85 Na 0.15 NCA electrode can generate more oxygen vacancies. • The MPD of the L 0.85 Na 0.15 NCA symmetrical electrode reached 1147 mW cm−2 at 550 °C. • The L 0.85 Na 0.15 NCA electrode remained stable at 550 °C for 108 h. [ABSTRACT FROM AUTHOR]

The pursuit of effective electrocatalysts for the oxygen evolution reaction (OER) is crucial for advancing sustainable energy technologies. Efficient OER catalysts play a vital role in the development of water splitting systems, which are fundamental for producing hydrogen—a clean and renewable energy source. The synthesis of IrO 2 nanoparticles embedded in ZIF-67 nanostructures has been explored to improve the performance of OER electrocatalysts. The resulting IrO 2 @ZIF-67 composite catalyst demonstrates a remarkable overpotential of 220 mV and 290 mV at current densities of 10 and 50 mA cm⁻2, alongside a low Tafel slope of 58 mV dec⁻1, significantly outperforming the pristine ZIF-67 catalyst. Integrating IrO 2 nanoparticles into the ZIF-67 matrix significantly enhances both the catalytic activity and durability of the material. Extensive electrochemical testing reveals that the IrO 2 @ZIF-67 catalyst maintains exceptional stability, operating consistently for over 50 h at a current density of 50 mA cm⁻2 without significant degradation. This enhanced performance is attributed to the synergistic effects between the highly active IrO 2 nanoparticles and the robust ZIF-67 framework, which collectively facilitate efficient charge transfer and improve structural integrity during prolonged OER operation. These findings highlight the potential of IrO 2 @ZIF-67 nanostructures as a promising electrocatalyst for sustainable water splitting applications, providing a pathway towards the development of more efficient and durable OER catalysts. In this work, we synthesized IrO 2 nanoparticle-embedded ZIF-67 nanocomposite electrocatalysts and evaluated their activity toward the OER using reduced amounts of IrO 2. The IrO 2 @ZIF-67 (DC) catalyst demonstrated superior OER performance, requiring an overpotential of 220 mV at 10 mA cm⁻2 (without iR correction) and exhibiting high mass and specific activities. The composite material maintained its catalytic activity over extended electrolysis periods, showing stability for over 50 h at a high current density of 50 mA cm⁻2. [Display omitted] • Investigated two approaches direct growth (hydrothermal) and drop casting (after hydrothermal). • IrO 2 @ZIF-67 catalyst requires 220 mV of overpotential at 10 mA cm−2 (without iR correction). • Mechanistic studies reveal the ZIF-67 framework in facilitating electron transfer and improving catalyst durability. [ABSTRACT FROM AUTHOR]

Proton exchange membrane water electrolysis (PEMWE) represents a promising avenue for producing hydrogen sustainably. Nonetheless, its widespread adoption encounters hurdles owing to the sluggishness of the oxygen evolution reaction (OER) and the expensive noble metal catalysts, particularly iridium (Ir). Our investigation addresses these challenges by examining pyrolusite β-MnO 2 as a robust substrate for noble metal catalysts, including iridium (Ir) and ruthenium (Ru), within PEMWE systems. We illustrate that nanostructured β-MnO 2 effectively supports Ir and Ru catalysts, resulting in significantly improved catalytic activity for acidic OER compared to conventional IrO 2 catalysts. The morphology shows nanorod structures with thicknesses ranging of 30–60 nm. The catalytic activity exhibits a lower overpotential of 215 mV and a higher Ir mass activity of 2268.7 A·g Ir −1. The catalyst also exhibits lower Tafel slope value (37.82 mV/dec) and higher reaction kinetics. The catalyst also shows durability for the 12h under corrosive acidic OER conditions. The enhancements in performance can be attributed to the distinctive nanostructure of the Mn 1-x Ti x O 2 (MTO) support, which facilitates the even distribution of Ir and Ru catalysts. Additionally, the incorporation of titanium in pyrolusite β-MnO 2 enhances the electrochemical durability of the MTO support under challenging acidic OER conditions. • Nanostructured β-MnO 2 has a superior intrinsic catalytic activity for PEMWE system. • Incorporation of titanium improved the electrochemical stability of β-MnO 2. • Ir–Ru-doped Mn 1-x Ti x O 2 has an excellent OER performance under acidic conditions. [ABSTRACT FROM AUTHOR]

The increasing concentration of CO₂ in the atmosphere, primarily driven by fossil fuel combustion, is a major contributor to global warming and one of the most pressing environmental challenges of the 21st century. In response, the development of sustainable energy technologies, such as hydrogen (H₂) production, has become crucial in the global transition to a low-carbon economy. In this study, we explored the catalytic activity of cobalt-modified niobium-based catalysts for hydrogen generation through the hydrolysis of NaBH₄. The catalysts were characterized using XRD, FTIR, XPS, SEM-EDX, and N₂ adsorption-desorption. XRD analysis revealed that the synthesized Nb₂O₅ (Nb₂O₅ Synt.) and Nb₂O₅/Co (Nb₂O₅/Co Synt.) exhibited amorphous structures, while the commercial Nb₂O₅ (Nb₂O₅ Com.) and its Co-modified composite displayed orthorhombic phases. The Nb₂O₅/Co Synt. catalyst achieved a surface area of 33.1 m2/g, significantly surpassing that of the commercial Nb₂O₅. The Nb₂O₅/Co Synt. catalyst exhibited superior catalytic activity, yielding 250 mL of hydrogen in 60 min, in contrast to other catalysts that showed no activity under identical conditions. This enhanced activity was attributed to the presence of surface hydroxyl groups and metallic Co nanoparticles, following the Langmuir-Hinshelwood bimolecular mechanism. Temperature was identified as a critical factor in the H₂ production rate, with a calculated activation energy of 11.37 kJ/mol. Moreover, the Nb₂O₅/Co Synt. catalyst demonstrated excellent reusability, maintaining stable performance after multiple reaction cycles, highlighting its potential for sustainable hydrogen production. [Display omitted] • Novel cobalt-modified niobium oxide catalyst for hydrogen production. • Critical role of hydroxyl groups in catalytic activity maintenance. • Comprehensive study of reaction parameters for optimized hydrogen generation. • Catalyst stability and reusability in multiple cycles. [ABSTRACT FROM AUTHOR]

Carbon nitride-based photocatalysts have great potential in producing hydrogen. Accelerating the separation and transfer of photogenerated electrons to the active site is an effective strategy to promote photocatalytic hydrogen evolution. However, it is typically constrained by a few active sites and the slow dynamics of photogenerated electron transfer. Loading metals as co-catalysts is a solution, but the cost limits its application. Here we report an atomic-scale photocatalyst modification strategy that can introduce boron into the three-coordinated C2 site of g-C 3 N 4. Under irradiation of 420 nm light, the apparent quantum efficiency (AQE) is 7.01%, which is higher than most of the reported B-doped g-C 3 N 4 under co-catalyst free. Detailed investigations indicate that the doped B has a stronger capacity to draw the photogenerated electrons and balance the adsorption-desorption of H∗, thereby substantially enhancing the performance of photocatalytic hydrogen production. This work provides new insights for the development of metal-free g-C 3 N 4 photocatalysts. When BCN–N-A is irradiated to produce a photogenerated charge, photogenerated electrons accumulate at the B site and reduce the protons adsorbed at the B site to form H 2 , while the holes oxidize the TEOA. [Display omitted] • The BCN–N-A photocatalyst exhibits highly efficient catalytic activity and stability. • Boron doping induced active site transfer of g-C 3 N 4. • The synergistic effect of cyano group and B-doped promotes the separation of photo-induced carriers. • A possible mechanism of hydrogen evolution is proposed. [ABSTRACT FROM AUTHOR]

Efficient and sustainable electrocatalysts for the hydrogen evolution reaction (HER) using earth-abundant elements are crucial for eco-friendly hydrogen production, particularly under neutral and acidic conditions. In metallic alloys, careful selection of alloying elements and control over the composition, morphology, electronic structure, and structural defects are expected to tune electrocatalytic activities. In this work, we introduce a two-step electrodeposition approach to create a 3D porous trimetallic alloy, Cu@Cu–Ni–Co, exhibiting excellent catalytic activity and stability for HER in neutral and acidic environments. The process begins with the electrodeposition of 3D copper dendrites, which was found to be crucial for the catalyst's mechanical stability, followed by the deposition of the trimetallic alloy, where copper's inclusion promotes the controlled growth of the alloy's 3D structure. The Cu@Cu–Ni–Co catalyst outperforms Cu@Ni, Cu@Co, Cu@Ni–Co, and GC@Cu–Ni–Co electrocatalysts in neutral and acidic conditions, highlighting the importance of the developed electrodeposition approach. In 1.0 M phosphate-buffer solution (PBS), Cu@Cu–Ni–Co achieves a current density of 10 mA cm−2 at an overpotential of 275 mV with a Tafel slope of 134 mV dec−1, maintaining remarkable stability in both acidic and neutral conditions at high current densities (48–165 mA cm−2) for up to 50 h without any decline in activity. [Display omitted] • Developed a two-step electrodeposition method to create a 3D porous Cu@Cu–Ni–Co alloy, optimizing HER performance in neutral and acidic conditions. • Used initial copper dendrite deposition for enhanced mechanical stability and precise microstructural control of the trimetallic alloy. • Achieved an overpotential of 275 mV with the Cu@Cu–Ni–Co catalyst, surpassing Cu@Ni, Cu@Co, Cu@Ni–Co, and GC@Cu–Ni–Co. • Maintained high stability at current densities of 48–165 mA cm−2 for 50 h without degradation, under both acidic and neutral conditions. • Demonstrated excellent compatibility and effectiveness on various substrates including glassy carbon, nickel foam, and ITO. [ABSTRACT FROM AUTHOR]

The design and construction of stable and inexpensive bifunctional catalysts for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) present a challenge in electrocatalytic water splitting. In this study, we utilized zeolitic imidazolate frameworks-8 (ZIF-8) as the precursor to fabricate ZnS-ZIF-8 via facile sulfidation processes. The ZnS-ZIF-8 nanostructures were anchored on the surface of the nickel nanowire (denoted as Ni NWs@ ZnS-ZIF-8 nanocomposite) and their catalytic activity for HER, OER, and overall water splitting were studied. The prepared Ni NWs@ ZnS-ZIF-8 revealed a low overpotentials value of 90 and 260 mV at 10 mA cm−2 for HER and OER in 1.0 M KOH solution, respectively. The alkaline electrolyzer assembled by Ni NWs@ ZnS-ZIF-8 provides a low cell voltage of 1.61 V at 10 mA cm−2 current density to boost the overall water splitting and robust stability for 15 h. The superior electrocatalytic activity of Ni NWs@ ZnS-ZIF-8 is owing to the facile and effective electron transport of Ni NWs, accessible active sites of ZnS-ZIF-8, and as well as the synergistic effect of the nanocomposite structures. This finding presents a viable methodology for synthesizing a proficient noble-metal-free catalyst for energy conversion and storage. [Display omitted] • Ni NWs@ S-ZIF8 composite was synthesized. • The as-prepared Ni NWs@ S-ZIF8 exhibits stability over 24 h. • The electrocatalyst revealed overpotentials of 90 and 260 mV at 10 mA cm−2 for HER and OER. [ABSTRACT FROM AUTHOR]

The exploration of bifunctional electrocatalysts with abundant resources and excellent catalytic performances is currently one of the fundamental conditions for the development and promotion of hydrogen energy technology. In this work, an extremely simple one-step hydrothermal strategy was proposed for the preparation of CoFe-layered double hydroxide nanosheets intercalated with molybdate (CoFe-LDH-MoO 4 2-). The well-designed electrocatalyst exhibits outstanding catalytic activity due to the adjustability of two-dimensional layered materials, synergistic effects of Co and Fe, as well as expanded inter-layer distance, which necessitates overpotential of 74 and 92 mV at 10 mA cm−2 for HER and OER, respectively. When the CoFe-LDH-MoO 4 2- is assembled in a two-electrode system, it requires a cell voltage of 1.50 V to drive 10 mA cm−2. The innovative exploration of this work offers a novel approach to construct multifunctional electrocatalysts for efficient and stable total water splitting. • A intercalation strategy is proposed to construct CoFe-LDH-MoO 4 2-. • CoFe-LDH-MoO 4 2- exhibits excellent overall water spitting performancesater splitting performance. • The enhanced electrocatalytical activity is due to the expanded interlayer distances. [ABSTRACT FROM AUTHOR]

The development of a catalyst exhibiting outstanding catalytic activity and robust stability for both the oxygen evolution reaction and hydrogen evolution reaction in alkaline media represents a substantial challenge. In this work, a NF/Ni@NiCoSP heterostructure bifunctional catalyst was developed via a sequent process of electrodeposition-hydrothermal-low temperature thermal pyrolysis sulphuration/phosphorization. The physical characterizations reveal that the as-prepared sample of NF/Ni@NiCoSP exhibits a porous nano-needles array structure and consists of both Ni 3 S 2 and Co 2 P phases with considerable boundaries. As a consequence, the NF/Ni@NiCoSP presents an ultralow overpotential of 47 mV and 260 mV at 10 mA cm−2 for hydrogen evolution reaction and oxygen evolution reaction, respectively. When assembled to a two-electrode system, it only requires 1.53 V to reach 10 mA cm−2, which surpasses the commercial RuO 2 ‖Pt/C (1.61 V). The methanol oxidation reaction probing experiment suggests the easy desorption of ∗OH from active sites due to the decreased binding strength between ∗OH and the catalyst, thus optimizing the kinetics condition. Moreover, the in-situ Raman spectra reveal that NiOOH and CoOOH serve as active sites for OER while the metal sites for HER. Therefore, this work introduces a feasible strategy to design cost-effective and robust catalysts with excellent catalytic properties, thereby paving the way for water splitting. • MOR probing experiment suggesting the easy desorption of ∗OH from active sites. • The NiOOH and CoOOH serve as active site for OER while the metal sites for HER. • NF/Ni@NiCoSP heterostructure bifunctional catalyst was developed. [ABSTRACT FROM AUTHOR]

Sluggish kinetics of oxygen evolution reaction (OER) is the main factor limiting the efficiency of water electrolysis. Heteroatom doping, interface engineering and compositing with conductive substrate are promising strategies to construct highly efficient electrocatalysts. Herein, several Zr and Fe co-doped crystalline cobalt with surface amorphous oxide layer wrapped in one-dimensional N-doped carbon fibers composite electrocatalysts have been prepared by pyrolyzing the electrospinning precursors in N 2 at 800 °C and followed by oxidizing in air at 200 °C. Mainly due to modulation of electron structure by Zr and Fe dopant and the interfacial effect of crystalline/amorphous heterostructure, the as-prepared catalysts exhibited excellent OER performances. As a result, only 374 mV of overpotential was needed for the optimized ZFCO@Co/CN-0.3:0.4:2.0 catalyst to reach 20 mA m- of current density. This work provides a new avenue for rational design of composite electrocatalysts for water splitting. Zr and Fe co-regulated cobalt-based one-dimensional composite fiber nanomaterials as highly efficient electrocatalysts for OER. Thanks to the heterogeneous structure, synergistic effect and one-dimensional fiber nanostructure, the prepared catalysts showed excellent OER catalytic activity and stability in alkaline media. [Display omitted] • Zr and Fe co-regulated cobalt wrapped in N-doped carbon fibers were prepared. • The surfaces of the metals were oxidized to form amorphous oxides layer. • Interfacial effect was exhibited in the crystalline/amorphous heterostructure. • Highly synergistic effect was exhibited among the multiple components. • The optimized catalyst exhibited superior OER electrocatalytic activity than RuO 2. [ABSTRACT FROM AUTHOR]

Using affordable electrocatalysts to produce hydrogen electrochemically by hydrolysis in an alkaline electrolyte is essential for addressing the energy of world crises and pollution issues. In this study, we have successfully synthesized MoS 2 -Ni 3 S 2 -CNTs/NF electrodes using a simple one-step hydrothermal method. These electrodes feature a multistage layered micro-nanostructure on nickel foam (NF) and exhibit super-hydrophilicity. The multilayered micro-nanostructure enhances the electrode's hydrophilicity, which promotes the exposure of active sites and accelerates electrolyte delivery. Notably, at a current density of 50 mA cm−2, these electrodes demonstrate excellent catalytic performance under alkaline conditions, with overpotentials of just 169 mV (approximately 0.59 times that of MoS 2 -CNTs/NF) for the hydrogen evolution reaction (HER) and 255 mV (approximately 0.57 times that of MoS 2 -CNTs/NF) for the oxygen evolution reaction (OER). Furthermore, the electrodes show remarkable stability, maintaining performance over an 8-h continuous operation at a constant overpotential. This work offers a novel approach to enhance electrocatalytic water splitting efficiency by structural and wettability manipulation, hence creating a new avenue for the generation of clean energy. • MoS 2 -Ni 3 S 2 -CNTs electrodes synthesized via a simple one-step hydrothermal method. • MoS 2 -Ni 3 S 2 -CNTs electrodes feature multistage micro- and nanostructured layered architecture. • MoS 2 -Ni 3 S 2 -CNTs exhibit outstanding bifunctional catalytic activity for water electrolysis. • CNTs incorporation creates a super-hydrophilic surface, enhancing catalytic efficiency. [ABSTRACT FROM AUTHOR]

Developing electrode materials with improved catalytic activity is inevitable (i) to achieve efficient electro-catalytic water splitting (EWS) and (ii) to construct high performance dye sensitized solar cells (DSSCs). To this aim, Nitrogen (N)-doped carbon-wrapped bimetallic CoCu alloys (i.e, CN@CoCu) are prepared by directly annealing the Cu-loaded Zeolitic Imidazolate Framework-67 (ZIF-67) metal-organic framework (MOF) and employed as (i) working electrode in EWS and (ii) counter electrode (CE) in DSSCs. The ZIF-67 MOF acts as a self-sacrificing template for the formation of CN@CoCu electrodes, whose electro-catalytic activity can be optimized by tuning the Co/Cu molar ratio (Cu = 0, 5%, 10%, 15% and 20%). The addition of 15% of Cu into the ZIF-67 (i.e., CN@CoCu-15), as the working electrode in water splitting has achieved lowest overpotential values of 91 and 256 mV towards hydrogen evolution reaction and oxygen evolution reaction, respectively. Also, for DSSCs applications, the same CN@CoCu-15 sample as CE displays an improved catalytic activity by 21% higher than that of conventional Pt CE towards tri-iodide redox reaction. Consequently, the CN@CoCu-15 based DSSCs device has achieved a PCE of 7.10% which is larger than that of conventional platinum CE (6.69%). The mechanism behind the improved catalytic activity is attributed to the significant reduction in the work function of CN@CoCu-15 (4.82 eV) compared to CN@Co (5.2 eV), as evidenced from Kelvin Probe Force Microscopic analysis. These findings proposed an efficient bifunctional electro-catalytic material with improved water-splitting performance and solar energy conversion. [Display omitted] • Carbon-wrapped CoCu electrode is prepared for water splitting and DSSC application. • The work function of the electrocatalyst is minimum (4.87) when Co/Cu ratio is 15. • It displays excellent catalytic activity towards KOH and triiodide electrolyte. • Water splitting has been achieved at 1.53 V with prepared CN@CoCu-15. • In DSSC, a PCE of 7.10 % is achieved with prepared CN@CoCu-15 as counter electrode. [ABSTRACT FROM AUTHOR]

The slow kinetics of oxygen evolution reactions (OER) have impeded the advancement of water splitting technology. Therefore, developing active, stable, and cost-effective electrocatalysts for the OER is crucial. In this study, we present the preparation of a porous Ni–Al rich phase high entropy alloy via the converse selective phase dissolution (CSPD) method. The research findings demonstrate that Fe–Cr rich phase can be removed in aqua regia etching solutions, leaving the non noble Ni–Al rich phase unaffected. Compared to bulk high entropy alloys, the porous structure provides a larger specific surface area and mass transfer channel for the OER. Additionally, the synergetic chemical effects of the high entropy alloy enhance the intrinsic reactivity of the electrode towards the OER. The porous Ni–Al rich phase HEA electrocatalysts exhibit a low OER overpotential of only 240 mV at 10 mA cm−2 and a Tafel slope of 47.1 mV dec−1 in 1.0 M KOH. Density functional theory (DFT) results indicate that the Ni–Al rich phase facilitates the transformation of ∗O to ∗OOH, resulting in superior OER performance compared to the Fe–Cr rich phase. This study introduces a novel strategy for preparing efficient, stable, and noble metal-free electrocatalysts for OER. [Display omitted] • A porous Ni–Al rich phase HEA with ultrahigh catalytic activity is synthesized via a facile CSPD method. • The electrode can stably deliver 10 mA cm−2 at only 240 mV and 47.1 mV dec−1 for OER. • Compared with the rich Fe–Cr phase, the rich Ni–Al phase facilitates the transition from ∗ O to ∗ OOH. [ABSTRACT FROM AUTHOR]

The cathodic catalytic activity for the oxygen reduction reaction (ORR) plays a critical role in determining the performance of proton-conducting solid oxide fuel cells (P-SOFCs). BaCo 0.4 Fe 0.4 Zr 0.2 O 3-δ (BCFZ) has emerged as a promising cathode for P-SOFCs due to its triple-phase conductivity. Nevertheless, its suboptimal proton conductivity and hydration ability at intermediate temperatures prevent it from achieving the anticipated ORR catalytic activity. To address these limitations, this study explores the enhancement of electrocatalytic activity in BCFZ through alkali metal doping and A-site defect construction. The effects of such modifications on oxygen surface exchange kinetics and ORR catalytic activity are systematically investigated. The findings reveal that BCFZ exhibits relatively low parameters in terms of electronic conductivity, oxygen ion conductivity, oxygen vacancy concentration, k chem , and D chem. Conversely, these parameters are markedly improved in A-site deficient BCFZ (D-BCFZ) and Na/K-doped BCFZ. Consequently, the enhancement of these properties yields a significant increase in ORR catalytic activity, with D-BCFZ demonstrating the best electrochemical performance. Specifically, P-SOFC with D-BCFZ cathode achieves an R p value of just 0.073 Ω cm2 and a P max value of 0.928 W cm−2 at 650 °C. This study provides theoretical insight into the mechanisms by how alkali metal doping and defect construction enhance the ORR catalytic activity of BCFZ. These findings offer valuable guidance for the development and optimization of high-performance P-SOFC cathodes. [ABSTRACT FROM AUTHOR]

Persistent phosphors possess unique afterglow optical properties. In this paper, a class of ultra-violet (UV) persistent luminescence nanoparticles were developed for catalytic photodegradation applications. UV persistent luminescence nanoparticles of SiO 2 -Zn 2 SiO 4 :Ga and SiO 2 -Zn 2 SiO 4 :Ga,Pb were successfully synthesized by using a mesoporous template method. The UV persistent luminescence intensity of SiO 2 -Zn 2 SiO 4 :Ga at 405 nm was enhanced up to ca. 3.5 times by co-doping with Pb2+ (396 nm), along with longer persistent luminescence duration. The photodegradation results indicate that it is useful to introduce UV persistent luminescence property into SiO 2 -Zn 2 SiO 4 :Ga,Pb to obtain enhanced catalytic activity of SiO 2 -Zn 2 SiO 4 with a bigger catalytic oxidation reaction kinetic constant (up to ∼4 times). This kind of UV persistent catalysis strategy may become a potential feasible method for better catalytic photodegradation activity. The UV persistent photocatalyst has potential applications in the photooxidation of organic molecules in high chroma and/or turbidity aqueous systems. [ABSTRACT FROM AUTHOR]