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The development of robust and efficient photocatalytic constructs for boosting the water oxidation reaction (WOR) is needed for establishing a sunlight-driven renewable energy infrastructure. Here, we synthesized plasmonic core–shell nanoconstructs consisting of triangular gold nanoprism (AuTNP) core with mixed manganese oxide (MnOx) shell for photoelectrocatalytic WOR. These constructs show electrocatalytic WOR with a low onset overpotential requirement of 270 mV at pH 10. Photoexcitation showed further enhancement of their catalytic activity resulting in ∼15% decrease of the onset overpotential requirement along with the generation of photocurrent density of up to 300 μA/cm2. We showed that such light-driven enhancement of AuTNP@MnOx dyad's catalytic activity toward the WOR process includes contributions from both photocatalytic (hot carriers driven) and photothermal effects with photothermal effect playing the major role for wavelength between 532 and 808 nm. The contribution from the photocatalytic effect is appreciable only for high-energy excitations near the interband region, while the photothermal effect largely dominates for lower energy excitations near the LSPR wavelengths of the dyad. [ABSTRACT FROM AUTHOR]

Classical theories of enzyme inhibition kinetics predict a monotonic decrease in the mean catalytic activity with the increase in inhibitor concentration. The steady-state result, derived from deterministic mass action kinetics, ignores molecular noise in enzyme-inhibition mechanisms. Here, we present a stochastic generalization of enzyme inhibition kinetics to mesoscopic enzyme concentrations by systematically accounting for molecular noise in competitive and uncompetitive mechanisms of enzyme inhibition. Our work reveals an activator-inhibitor duality as a non-classical effect in the transient regime in which inhibitors tend to enhance enzymatic activity. We introduce statistical measures that quantify this counterintuitive response through the stochastic analog of the Lineweaver–Burk plot that shows a merging of the inhibitor-dependent velocity with the Michaelis–Menten velocity. The statistical measures of mean and temporal fluctuations - fractional enzyme activity and waiting time correlations - show a non-monotonic rise with the increase in inhibitors before subsiding to their baseline value. The inhibitor and substrate dependence of the fractional enzyme activity yields kinetic phase diagrams for non-classical activator-inhibitor duality. Our work links this duality to a molecular memory effect in the transient regime, arising from positive correlations between consecutive product turnover times. The vanishing of memory in the steady state recovers all the classical results. [ABSTRACT FROM AUTHOR]

The interaction between adjacent active sites is crucial to balance the efficiency and utilization of functional atoms in single-atom catalysts. Herein, the catalytic activity of hydrogen evolution reaction at different site (nitrogen coordinated transition metal centers embedded in graphene) distances was comprehensively investigated by density functional theory calculations. The results show that a proximity effect of reactivity and site spacing can be identified in the Co-series single-atom catalysts. Although the proximity effect is more linearly responded with the site spacing along x direction, an optimal distance of ∼0.8 and ∼2.8 nm are found for Co and Rh, Ir atoms, respectively. An in-depth analysis of the electronic property reveals that the proximity effect is caused by the distinct net charge of the active site, which is affected by the d z 2 position relative to EF. Subsequently, an excess electron nodal channel in x direction was found to serve as a communication pathway between the active sites. Through the finding in this work, an optimal Fe-N2C2 structure was deliberately designed and has shown prominent proximity effect as Co-series do. The results reported in this work provide a simple and effective tuning method for the reactivity of a single-atom catalyst. [ABSTRACT FROM AUTHOR]

Piezo-photocatalysis is a "green" approach to decompose various pollutants using natural clean energy. Herein, a series of ZnSnO 3 /C nanofibers with excellent piezo-photocatalytic activities were reported. The XRD, TEM and SEM, as well as XPS measurements were carried out and the results indicate that ZnSnO 3 /C nanofibers with the orthorhombic phase were fabricated successfully. The UV–vis absorbance spectra, photocurrent response, EIS curves and photoluminescence characteristics indicate that the incorporated C decreases the band gap of ZnSnO 3 and improves separation efficiency of photoinduced charge-hole pairs, which results in higher catalytic activity of ZnSnO 3 /C nanofibers. The photocatalytic, piezocatalytic and piezo-photocatalytic activities were investigated by degrading diclofenac. The ZnSnO 3 /C‒0.3 ‰ has the highest reaction constant among the series of catalysts. The reaction constat of ZnSnO 3 /C‒0.3 ‰ in photocatalysis process (0.0185 min−1) is 2.15 times that of ZnSnO 3. The reaction constat of ZnSnO 3 /C‒0.3 ‰ in piezo-photocatalysis process (0.0549 min−1) is 2.97 times that of ZnSnO 3 /C‒0.3 ‰ in photocatalysis and 3.47 times that of ZnSnO 3 in piezo-photocatalysis (0.0158 min−1). The •OH and e− radicals are key roles for degrading diclofenac in catalysis processes. [ABSTRACT FROM AUTHOR]

The influence of the heterogeneous interface is critical for the catalytic activity of the oxygen reduction reaction (ORR). This study demonstrates an enhancement of the electrocatalytic activity of the SrFe 0.9 Nb 0.1 O 3-δ (SFN113) electrode through the construction of a SrFe 0.9 Nb 0.1 O 3-δ -Sr 3 Fe 1.8 Nb 0.2 O 7-δ (SFN113-SFN327) heterogeneous interface. By coating varying amounts of Sr(NO 3) 2 (0.1 g, 0.2 g and 0.3 g) on SFN113 (1 g), SFN113/327 composite electrodes with different amounts of triple conducting oxide SFN327 are in-situ synthesized by high temperature calcination. Electrical Conductivity Relaxation (ECR) tests show that SFN327 has superior oxygen surface exchange performance compared to SFN113, especially at lower temperatures. At 550 °C, the oxygen surface exchange parameter of SFN327 is 4.23 times higher than that of SFN113. Symmetric cell tests with SFN113/327||BaCe 0.7 Zr 0.1 Y 0.1 Yb 0.1 O 3-δ (BCZYYb)||SFN113/327 configuration and single cell tests with Ni-BCZYYb||BCZYYb||SFN113/327 configuration indicate that the SFN113/327 composite electrode with a mass ratio of 1:0.2 displays the best electrocatalytic performance, achieving a power output of 502 mW cm−2 at 700 °C. The work not only in-situ synthesizes the SFN113/327 triple conducting composite electrode, but also introduces a novel method for developing proton conducting electrode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient descriptor of catalytic activity (ΔE NH2*) was developed. • A descriptor-based design principle was proposed. • Constructing bimetallic MBene can promote the NRR catalytic performance. • Bimetallic MBene break linear scaling relations between ΔE NHNH2** and ΔE NH2NH2**. Electrocatalytic nitrogen reduction reaction (NRR) is one of the most promising approaches to achieving green and efficient NH 3 production. However, the designs of efficient NRR catalysts with high activity and selectivity still are severely hampered by inherent linear scaling relations among the adsorption energies of NRR intermediates. Herein, the properties of ten M 3 B 4 type MBenes have been initially investigated for efficient N 2 activation and reduction to NH 3 via first-principles calculations. We highlight that Cr 3 B 4 MBene possesses remarkable NRR activity with a record-low limiting potential (−0.13 V). Then, this work proposes descriptor-based design principles that can effectively evaluate the catalytic activity of MBenes, which have been further employed to design bimetallic M 2 M'B 4 MBenes. As a result, 5 promising candidates including Ti 2 YB 4 , V 2 YB 4 , V 2 MoB 4 , Nb 2 YB 4 , and Nb 2 CrB 4 with excellent NRR performance have been extracted from 20 bimetallic MBenes. Further analysis illuminates that constructing bimetallic MBenes can selectively tune the adsorption strength of NHNH 2 ** and NH 2 NH 2 **, and break the linear scaling relations between their adsorption energies, rendering them ideal for NRR. This work not only pioneers the application of MBenes as efficient NRR catalysts but also proposes rational design principles for boosting their catalytic performance. [ABSTRACT FROM AUTHOR]

Glutathione-mediated copper sulfide nanoplatforms with morphology and vacancy dependent photothermal catalytic activity for multi-model tannic acid assays. [Display omitted] Interface engineering and vacancy engineering play an important role in the surface and electronic structure of nanomaterials. The combination of the two provides a feasible way for the development of efficient photocatalytic materials. Here, we use glutathione (GSH) as a coordination molecule to design a series of Cu x S nanomaterials (Cu x S-GSH) rich in sulfur vacancies using a simple ultrasonic-assisted method. Interface engineering can induce amorphous structure in the crystal while controlling the formation of porous surfaces of nanomaterials, and the formation of a large number of random orientation bonds further increases the concentration of sulfur vacancies in the crystal structure. This study shows that interface engineering and vacancy engineering can enhance the light absorption ability of Cu x S-GSH nanomaterials from the visible to the near-infrared region, improve the efficiency of charge transfer between Cu x S groups, and promote the separation and transfer of optoelectronic electron-hole pairs. In addition, a higher specific surface area can produce a large number of active sites, and the synergistic and efficient photothermal conversion efficiency (58.01%) can jointly promote the better photocatalytic performance of Cu x S-GSH nanomaterials. Based on the excellent hot carrier generation and photothermal conversion performance of Cu x S-GSH under illumination, it exhibits an excellent ability to mediate the production of reactive oxygen species (ROS) through peroxide cleavage and has excellent peroxidase activity. Therefore, Cu x S-GSH has been successfully developed as a nanoenzyme platform for detecting tannic acid (TA) content in tea, and convenient and rapid detection of tannic acid is achieved through the construction of a multi-model strategy. This work not only provides a new way to enhance the enzyme-like activity of nanomaterials but also provides a new prospect for the application of interface engineering and vacancy engineering in the field of photochemistry. [ABSTRACT FROM AUTHOR]

Fourteen new phenoxy-azo aluminium complexes comprising two series, namely, dimethyl{phenoxy-azo}aluminium complexes 1a–7a and monomethyl{phenoxy-azo}aluminium complexes 1b–7b, were successfully synthesised and characterised. The molecular structure of complex 4a, determined using X-ray diffraction analysis, displayed a distorted tetrahedral geometry. The 1H NMR spectrum of complex 5b revealed fluxional behaviour caused by isomeric transformation that occurs in the solution at room temperature. The activation parameters determined by lineshape analysis of variable-temperature 1H NMR spectra in toluene-d8 are as follows: ΔH‡ = 70.05 ± 1.19 kJ mol−1, ΔS‡ = 21.78 ± 3.58 J mol−1 K−1 and ΔG‡ (298 K) = 63.56 ± 0.11 kJ mol−1. All aluminium complexes are active initiators for the ring-opening polymerisation of rac-lactide, and the polymerisations proceeded in a controlled manner and were living. In comparison, the catalytic activity of the dimethyl{phenoxy-azo}aluminium complexes was insignificantly different from that of the corresponding monomethyl{phenoxy-azo}aluminium complexes. The steric factor of the ortho-phenoxy substituent was observed to exert a decelerating effect on the catalytic rate. Kinetic investigations revealed first-order dependency on both monomer and initiator concentrations. Comparative catalytic investigations conducted on phenoxy-azo aluminium and phenoxy-imine aluminium complexes revealed that the former complexes exhibited lower catalytic activity. [ABSTRACT FROM AUTHOR]

A series of novel diphosphinoamine (PNP) ligands bearing a P-alkenyl group were synthesized and applied in chromium-catalyzed selective ethylene tri-/tetramerization by in situ combination of Cr(acac)3 and modified methylalumoxane (MMAO-3A). The ligand substitution and oligomerization conditions have a remarkable influence on the catalytic activity and controllable selectivity. Most of these PNP ligands are highly active for ethylene tri-/tetramerization with considerable selectivity. An asymmetric diisopropenylphosphanyl ligand with an N-cyclohexyl group achieved the highest activity of 2036 kg (g Cr h−1)−1 with a high total selectivity of 81.1 wt% toward valuable 1-hexene (43.0 wt%) and 1-octene (38.1 wt%) at 40 bar ethylene and 60 °C. An asymmetric mixed isopropenyl/ethylphosphanyl ligand with an N-isopropyl group exhibited a high 1-octene selectivity of 65.5 wt% and a high total 1-hexene/1-octene selectivity (91.5 wt%) with a high activity of 1256 kg (g Cr h−1)−1. [ABSTRACT FROM AUTHOR]

Direct synthesis of dimethyl carbonate (DMC) from CO2 and CH3OH holds significant economic and environmental value. Numerous catalysts have been employed for this reaction, yet further enhancement of its activity requires a deeper understanding of the catalyst's structure–activity relationship and catalytic mechanism. In this study, we utilized structurally well-defined and highly tunable MOF-808 as a research platform. Functionalizing MOF-808 with ethylenediamine (MOF-808-ED) boosted the space time yield of DMC from 3.25 mmol g−1 h−1 to 7.23 mmol g−1 h−1. The experimental results demonstrate that the reaction involves acid–base synergistic catalysis, where an appropriate balance of acid–base site content is crucial for CO2 and CH3OH to produce DMC, as it facilitates the formation of the key intermediates (CH3OCOO*). Additionally, the nucleophilicity of N is stronger than that of O, further promoting the catalyst's enrichment and activation of CO2. Finally, employing in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) testing, we elucidated the mechanism by which the MOF-808-ED catalyst, with –NH2 as base sites and Zr as acid sites, facilitates the synergistic catalysis of the reaction. This study provides insights into the synergistic effects of acid–base sites on the synthesis of DMC from CO2 and methanol, offering valuable guidance for the development of high-performance catalysts. [ABSTRACT FROM AUTHOR]

For the upcycling of waste polyethylene terephthalate (PET), encompassing both colored and fabric PET materials, we investigated the Ir(triNHC)‐catalyzed dehydrogenative coupling of PET and methanol, leading to the production of sodium lactate with good yields. We proposed a sustainable method for isolating lactic acid from the catalytic reaction mixture of sodium lactate and regenerating the base using bipolar membrane electrodialysis (BMED). This isolation method demonstrated high effectiveness, achieving isolation of lactic acid while maintaining economic feasibility at $ 0.10 per kg of lactic acid, and enabling sustainable NaOH regeneration with complete resource circulation. We assessed the recyclability of the catalyst and elucidated the mechanism involving base‐mediated depolymerization and catalyst‐promoted dehydrogenation, highlighting the importance of triNHC ligands in enhancing catalytic activity. [ABSTRACT FROM AUTHOR]

Although Ru‐based materials are among the outstanding catalysts for the oxygen evolution reaction (OER), the instability issue still haunts them and impedes the widespread application. The instability of Ru‐based OER catalysts is generally ascribed to the formation of soluble species through the over‐oxidation of Ru and structural decomposition caused by involvement of lattice oxygen. Herein, an effective strategy of selectively activating the lattice oxygen around Ru site is proposed to improve the OER activity and stability. Our synthesized spinel‐type electrocatalyst of Ru and Zn co‐doped Co3O4 showed an ultralow overpotential of 172 mV at 10 mA cm−2 and a long‐term stability reaching to 100 hours at 10 mA cm−2 for alkaline OER. The experimental results and theoretical simulations demonstrated that the lattice oxygen site jointly connected with the octahedral Ru and tetrahedral Zn atoms became more active than other oxygen sites near Ru atom, which further lowered the reaction energy barriers and avoided generating excessive oxygen vacancies to enhance the structural stability of Ru sites. The findings hope to provide a new perspective to improve the catalytic activity of Ru‐incorporated OER catalysts and the stability of lattice‐oxygen‐mediated mechanism. [ABSTRACT FROM AUTHOR]

Hydrogen production through electrocatalytic water splitting or urea splitting has been considered one of the most fascinating methods to relieve the energy pressure. In this paper, the effects of Zr introduction on formation of NiFe 2 O 4 and catalytic activity are studied. Using oxygen evolution and urea oxidation as concerned reactions, the effects of different dosage on the catalytic performance of the materials were performed. It was found that the Zr–NiFe LDH@NiFe 2 O 4 /NF-1 material exhibited superior water oxidation properties (overpotential of 290 mV @100 mA cm−2). For urea oxidation reaction, the catalytic performance of this NiFe LDH material is better at low current density. However, at high current densities, this Zr–NiFe LDH@NiFe 2 O 4 /NF-1 electrode exhibits better electrochemistry performance. It is proved that the oxidation of water also contributes a part of the activity under large current. Density functional theory also suggests that the NiFe 2 O 4 material is favorable for water adsorption. This work will provide novel opinion for the development of environmentally friendly and low cost materials. It was found that the Zr–NiFe LDH@NiFe 2 O 4 /NF-1 material exhibited superior water oxidation properties (overpotential of 290 mV @100 mA cm−2). [Display omitted] • The formation of this NiFe LDH and NiFe 2 O 4 material can be induced by modulating the content of Zr. • The Zr–NiFe LDH@NiFe 2 O 4 presents a improved activity with small overpotentials of 290 mV for water oxidation. • The increase of performance is ascribed to the accelerated charge transfer and promoted electrolyte transfer. [ABSTRACT FROM AUTHOR]

Constructing the interface of Ni/Y 2 O 3 heterogeneous catalyst is a feasible strategy for efficient catalyst design in CO 2 methanation, which can create the active Y–O–Ni interfacial sites by utilizing the interaction between Ni and Y 2 O 3. In this work, the strategy of using different nickel precursors (nickel nitrate, nickel acetate, basic nickel carbonate and nickel citrate) was used to prepare various Ni-based catalysts supported on Y 2 O 3 , which were estimated for their catalytic performance on CO 2 methanation. The catalysts were characterized based on BET, XRD, TEM, H 2 -TPR, XPS and CO 2 -TPD, etc. The results indicated a close correlation between the metal dispersion and particle size of Ni/Y 2 O 3 catalysts and the nickel precursor employed. The Y–O–Ni interface structure in Ni/Y 2 O 3 catalysts, associated with basic sites, provides a richer source of basic sites, offering more active sites for CO 2 adsorption and activation. Ni/Y 2 O 3 catalyst prepared with nickel nitrate as the precursor exhibited characteristics such as a highly enhanced nickel dispersion, a smaller nickel particle size, and more abundant metallic Ni0 sites. Moreover, nickel nitrate-derived Ni/Y 2 O 3 catalyst exhibited optimal catalytic activity, achieving a CO 2 conversion rate of up to 92 % at 300 °C, with 100 % selectivity to CH 4 , and displaying good stability over 30 h. Therefore, the dispersion of Ni and the size of Ni particles could be controlled by adjusting the precursor, which is closely associated with the catalytic activity of Ni/Y 2 O 3 catalyst. This work unveils the interface-property relationship of Ni/Y 2 O 3 catalysts and provides a new insight into strategy of constructing more effective Ni-based catalyst for CO 2 methanation through the controlled nickel precursor. [Display omitted] • The catalytic performance and properties of Ni/Y 2 O 3 is influenced by the Ni precursor in CO 2 methanation. • Ni–N exhibits superior activity at 300 °C achieving a CO 2 conversion of 92 % at 300 °C, with 100 % selectivity to CH 4. • The nickel precursor influences the particle size of Ni and the metal-support interaction. • The Y–O–Ni interface structure in Ni/Y 2 O 3 is associated with basic and metallic Ni sites. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of novel polythiophene (PTh)-based electrocatalysts incorporating NiCo-LDH and NiCo 2 S 4 additives for oxygen evolution reaction (OER) are investigated. NiCo-LDH and NiCo 2 S 4 are synthesized using standard precipitation techniques and characterized using X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and scanning electron microscopy (SEM). PTh-based composite coatings are electrodeposited on steel substrates with varying concentrations of NiCo-LDH and NiCo 2 S 4. The electrochemical performance of the composite coatings is evaluated using linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), and stability tests. Results reveal that the incorporation of NiCo-LDH and NiCo 2 S 4 enhances the catalytic activity of PTh-based electrocatalysts for OER, with PTh@NiCo 2 S 4 exhibiting superior performance. The synergistic effects of the additives improve charge transfer kinetics and interfacial conductivity, leading to efficient oxygen generation. The study demonstrates the potential of tailored composite materials for advancing sustainable energy conversion technologies. • Novel PTh-based electrocatalysts incorporating NiCo-LDH and NiCo 2 S 4 enhance OER catalysis. • Synergistic effects improve charge transfer kinetics and interfacial conductivity. • Structural disparities influence catalytic activity, with PTh@NiCo 2 S 4 exhibiting superior performance. • Unexpected findings challenge conventional beliefs on the correlation between C dl and catalytic activity. • Tailored composite materials offer promising avenues for advancing sustainable energy conversion technologies. [ABSTRACT FROM AUTHOR]

Hydrogen liquefaction is one of the main methods for hydrogen energy applications, and obtaining a high para-hydrogen concentration is an indispensable part of the storage and transportation of liquid hydrogen. Therefore, the preparation and research of catalysts to accelerate ortho-para hydrogen conversion (OP conversion) is an important method to solve the problem of liquid hydrogen storage and transportation. In this paper, we demonstrate the catalytic effect of metal-organic frameworks (MOFs) on OP conversion at 77 K. The crystal structure, morphology and magnetization of the catalyst were discussed by using XRD, BET, FTIR, VSM and other characterization techniques. Among them, Ni-BTC (Ni-based MOF material synthesized from H 3 BTC and Ni2+) has the highest catalytic activity, and the conversion efficiency reaches the highest value of 91.4% when the GHSV (Gas Hourly Space Velocity) is 12000 h−1, which opens a new way for the design and synthesis of catalytic materials for OP conversion. [Display omitted] • The catalytic performance of M-BTC for ortho-para hydrogen conversion was studied. • The structure of M-BTC can be adjusted by changing different metal bases. • M-BTC exhibits the best catalytic performance when Ni is the metal center. • Ni-BTC has the highest conversion efficiency of 91.4% when the GHSV is 12000 h-1. [ABSTRACT FROM AUTHOR]

We synthesized a bismuth-MOFs@CNTs (BiBTC@CNTs) catalyst using a microwave-assisted solvothermal method. The mass ratios of CNTs and BiBTC varied from 0 to 2, 5, and 10% (denoted as BiBTC@CNTs-x, x = 0 to 2, 5, and 10). The characteristics of the catalyst were determined by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and diffuse reflectance spectroscopy (UV-Vis DRS). The catalytic activity of the material was tested by photodegradation of rhodamine B. The structure of BiBTC@CNTs-x displayed a UU-200 and CNT structure with rod-shaped interweaving between the CNT fibers. The results indicated that BiBTC@CNTs-2 had the most significant ability to degrade RhB, achieving 98% degradation in 180 min. The increased separation of electron-hole pairs via a built-in electric field between CNT and BiBTC is responsible for the improved photocatalytic degradation of RhB, as observed in the XPS spectrum, transient photocurrent response, electrochemical impedance spectroscopy (EIS), and Mott-Schottky plots. In addition, the catalyst mass, dye concentration, pH of the medium, and radical scavengers were investigated. Furthermore, free radicals (O2−) and electrons (e-) played the primary and most influential role in the photocatalytic degradation of both dyes, with a minor contribution from the photogenerated holes (h+). Kinetic study of the dye degradation process followed a first-order kinetic model. [ABSTRACT FROM AUTHOR]

In this study, an anionic dye, Reactive Black 5 (RB5), was subjected to sonophotocatalytic treatment process with the aim of establishing the effectiveness of the prepared ZnO incorporated activated red mud (ZnO/ARM) as a viable sonophotocatalyst. ZnO/ARM was prepared by impregnation method at different weight ratios (0.25:1, 0.5:1, 0.75:1 and 1:1) with the ZnO/ARM at weight ratio of 0.75:1 proving to be the best sonophotocatalyst. The prepared sonophotocatalysts were characterized by X-ray diffractometer for crystal phase studies, Brunauer–Emmett–Teller for surface area studies, Fourier transform infrared for surface functional groups studies, SEM–EDX for surface morphological and elemental studies, diffuse reflectance spectroscopy and photoluminescence for sonophotocatalyst band-gap studies while parametric and kinetic studies of the removal of RB5 from the simulated wastewater were conducted to confirm its effectiveness under simultaneous application of a transducer bath-type sonicator (35 kHz) and a UV-C (254 nm) lamp. The influence of the solution pH, concentration and catalyst dosage were manipulated throughout this study to investigate the sonophotodegradation kinetics and synergistic effects on the RB5 degradation. Experimental results confirmed that the sonophotocatalytic degradation rate of 20 ppm RB5 was most effective under acidic medium (66.7%) as compared to alkaline medium (46.1%) due to an excess of positive charge in the ZnO/ARM surface which favours a strong electrostatic interaction with SO3− groups of the dye resulting in a higher degradation rate (0.0156 min−1). Under alkaline conditions, the catalytic activity of ZnO/ARM was attenuated by the higher negative charge which promoted the repulsion of the dye from ZnO/ARM surfaces leading to a lower degradation rate of 0.01 min−1. The accelerated photo induced electron–hole transfer and separation, decreased recombination rate and band energy matching, enhancing the photocatalytic performance of ZnO/ARM composite. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) is a promising way to produce the second generation biodiesel from aliphatic acid based biomass. In this study, NixMoy@NC bimetallic catalysts with varying molar ratios were prepared using ZIF-8 as a representative MOF precursor. Lauric acid was chosen as the model compound, the catalytic performance of these catalysts with different metal ratios, reaction temperatures, and pressures was investigated. In addition, the reaction of lauric acid, lauric alcohol, and lauric aldehyde at different reaction times were investigated to explore the pathways of lauric acid. The influence of Mo doping on the catalyst structure, reducibility, and electronic properties was investigated through a series of characterizations, including SEM, TEM, XPS, H2-TPR, and NH3-TPD. This study revealed that the ZIF-8 support with incorporated Ni and Mo maintained a stable structure. Compared to Ni-based catalysts, the addition of Mo in the bimetallic catalyst can bring the electron transfer between Ni and Mo and increased the active sites and acid sites. An appropriate amount of Mo can lower the reduction temperature and enhance the catalytic activity for hydrogenation and deoxygenation reactions. Based on the catalytic experimental results, it can be observed that liquid alkanes, such as undecane and dodecane, are primarily formed through decarbonylation of lauric aldehyde and hydrodeoxygenation of lauric alcohol. Additionally, under high-temperature conditions, the hydrodeoxygenation reaction is favored over the decarbonylation reaction, promoting the production of dodecane. This indicates that Mo exhibits better activation for the C–OH reaction, leading to these observations. Under repeated use, the catalyst still has good catalytic activity and stability. [ABSTRACT FROM AUTHOR]

Natural hematite supported cobalt (Co/Nat-Hem), a new heterogeneous catalyst, was successfully prepared by a simple impregnation technique. Textural, structural, functional groups and morphological aspects of the prepared catalyst were analyzed by BET, XRD, FT-IR, XRF, pHpzc, SEM-EDX methods. BET analysis shows that the Co/Nat-Hem catalyst has a specific surface area of ​​13.44 m2/g and a pore volume of 0.062 cm3/g. The SEM-EDX method showed that 7.19 wt% of the cobalt species were dispersed on the surface of the prepared catalyst. The catalytic activity of Co/Nat-Hem was evaluated by photo-Fenton oxidation of the dye Cong red (CR). The effect of reaction parameters on CR oxidation efficiency was investigated. Under optimal reaction conditions (1 g/L catalyst concentration, 0.2 mol/L H2O2 initial concentration and pH 3), the percentage of CR discoloration reaches 97% after 30 min. The Co/Nat-Hem catalyst achieved a synergistic ratio of 28.5%, which was added to the oxidation rate of the Nat-Hem catalyst. The stability of the Co/Nat-Hem catalyst was demonstrated by the limited activity of leachates in the homogeneous Fenton oxidation of CR. The phytotoxicity of the CR dye was tested during the irrigation of the bean (Vicia faba L.). [ABSTRACT FROM AUTHOR]

In this article, we have studied the influence of the heat treatment in an inert atmosphere on the structure and catalytic activity of the PtCu/C catalysts with an architecture of bimetallic nanoparticles obtained by a multi-step synthesis method. The transformation of the structure obtained by a multi-step synthesis method into a solid solution during the heat treatment at 350 °C has been shown by the methods of high-resolution TEM and XPS. It has been found that regardless of the type of a carbon support used, the heat treatment leads to an increase in the specific mass activity by 1.4–1.6 times. The increase in the catalytic activity after the heat treatment is achieved due to a change in the chemical composition of the surface and an increase in the degree of alloying of metal components. Due to the combination of the heat treatment and the use of a nitrogen-doped carbon support, we have succeeded in obtaining the PtCu/C catalyst, the ORR activity of which is 6.4 times higher than that of the commercial analog. Testing of the most promising samples as part of the MEA has confirmed the high quality of the materials obtained, the maximum power being 696 W/g (Pt) for the PtCu/C catalyst after the heat treatment. [ABSTRACT FROM AUTHOR]

Three new palladium(II)-iminophosphine complexes, [Pd(L1)(Cl)2] C1, [Pd(L2)(Cl)2] C2 and [Pd(L3)(Cl)2] C3 have been synthesized and successfully characterized by using 1H-NMR, 13C-NMR, 31P-NMR, UV–Vis, FT-IR and magnetic susceptibility techniques. Catalytic activities of complexes towards Suzuki–Miyaura C–C coupling reactions between phenylboronic acid and several aryl halides were investigated under several reaction conditions (solvent, temperature, base, reaction time, and type of substrate). Under optimum conditions, achieving high yields of up to 99% was possible. When 1-bromo-4-nitrobenzene was used for complex C1, bromobenzene for complex C2, and bromobenzene for complex C3, product yields of 99, 99, and 98% were achieved, respectively. Three new palladium complexes bearing iminophosphine ligands was synthesized and successfully characterized. Catalytic activities of the synthesized complexes were investigated on Suzuki–Myaura type coupling reaction between phenylboronic acid and several aryl halides. All complexes exhibited good catalytic activities on C–C coupling reactions up to 99% product formations under mild conditions. [ABSTRACT FROM AUTHOR]

Mono-derivatives of fullerene C60 with l-phenylalanine, o-fluoro-l-phenylalanine and p-fluoro-l-phenylalanine, as well as their hybrid nanostructures with derivatives of vitamin B12, have been synthesised. The structure of the compounds was determined by IR, UV and CD-spectroscopy. The IR spectra of the obtained compounds contain all bands characteristic of the original compounds, with the exception of the band at 1227 cm−1, which is related to the free carboxyl group in the fullerene fragment. In the UV spectra of hybrid nanostructures contain smoothed peaks in the region of 360 nm, confirming the presence of corrin ligand in the original and obtained compounds. Using the CD method, it was found that all spectra have a characteristic maximum in the region of 430 nm, confirming the presence in all hybrids nanostructures of a fragment of vitamin B12: e-COOH-Cbi(OH)2. The radiuses of nanoparticles of hybrid nanostructures, calculated by the dynamic light scattering method, range from 90 to 120 nm. The degree of association in the complexes ranges from 400 to 600 thousand molecules. It was shown that the resulting hybrid nanostructure retains catalytic activity in the autoxidation reaction of ascorbic acid, inherent in derivatives of vitamin B12. [ABSTRACT FROM AUTHOR]

Piezocatalysis presents an innovative catalytic technique that utilizes the piezoelectric properties of catalysts to convert mechanical energy into electrical energy, thereby driving chemical processes. While various methods for driving piezocatalytic reactions have been developed, there is a notable absence of comprehensive research on piezocatalytic performance across multiple methods. In this context, this study explores the potential of (1- x)Pb(Ni 1/3 Nb 2/3)O 3 - x PbTiO 3 (PNN-PT) based catalysts as efficient piezocatalysts using both ultrasonic vibration and ball milling. The optimal reaction rate constants of the PNN-PT piezocatalyst under ultrasonic vibration and ball milling are found to be 0.0775 min−1 and 0.0265 min−1, respectively. Notably, PNN-PT-based catalysts exhibit outstanding catalytic activity up to ultra-high substrate concentrations (65 mg/L), suggesting possible industrial applications. The exploration of the reaction mechanism indicates that •OH is the main reactive radical, the catalytic reaction activity demonstrates a direct relationship with •OH quenching, and the high •OH generation rate of PNN-PT further illustrated their suitability as environmental purification catalysts. [ABSTRACT FROM AUTHOR]

Streptomycin was chosen as the test species, and MgO@graphene nanocomposites were created and assessed for their catalytic activity towards the breakdown of 4-NP. As a new catalyst with strong catalytic activity and good stability, MgO@graphene was used. It was discovered that this catalyst's catalytic activity was much increased in an acidic environment. It is suggested that the degradation mechanism is caused by MgO@graphene nanocomposites reacting with dissolved oxygen. This further demonstrates the obvious significance of graphene in serving as the MgO nanocatalyst's support. XRD results indicated that the majority of G species in MgO@ (0.25 g) G more strongly interacted with the MgO surface. The doped catalyst MgO@ (0.25 g) G reached its steady state activity faster than the other catalysts. The degree of MgO@G interaction decreased in the following S4 > S mix > S 2 > S 3 > S 1 > S5 > S 6 > S o . High degradation rate constants were found, and the amounts of streptomycin and 4-nitrophenol vary exponentially over time. It was demonstrated that, in most situations, the pseudo-first- order equation fits the degradation kinetics. Hence, in degrading systems, MgO NPs@Graphene nanostructures are thought to be a very effective and promising catalyst. [ABSTRACT FROM AUTHOR]

Preparation and study of FeOOH modified Co 9 S 8 composites were successful. The catalysts have abundant non-homogeneous interfaces between FeOOH and Co 9 S 8 nanosheets, which optimize the coordination environments of Fe and Co sites through the redistribution of interfacial charges. This results in appropriate chemisorption strength of oxygenated intermediates, leading to accelerated reaction kinetics, abundant active sites, and good OER properties. [Display omitted] • The FeOOH/Co 9 S 8 composites electrocatalyst was developed. • The redistribution of interface charges optimizes the coordination environment of Fe and Co sites. • Appropriate chemisorption strength of oxygenated intermediates. Efficient oxygen evolution reaction (OER) is vital for water electrolysis and advanced hydrogen energy production. However, the sluggish kinetics of this reaction require significant overpotentials, leading to high energy consumption. Therefore, developing OER electrocatalysts with exceptional performance and long-term durability is crucial for enhancing the energy efficiency and cost-effectiveness of the hydrogen production process. In this research, novel FeOOH/Co 9 S 8 catalysts were prepared through a two-step hydrothermal reaction followed by one-step electrodeposition on nickel foam for an alkaline OER. The as-obtained catalysts possessed abundant non-homogeneous interfaces between FeOOH and Co 9 S 8 nanosheets, conducive to optimized coordination environments of Fe and Co sites by redistributing interfacial charges. This synergy strengthened the chemisorption of oxygenated intermediates, leading to accelerated reaction kinetics, abundant active sites, and enhanced OER performance. The optimized electrocatalyst FeOOH/Co 9 S 8 -15 achieved a current density of 10 mA cm-2 at an overpotential of 248 mV and good stability for over 140 h. This study presents a novel approach for producing compelling and durable alkaline dielectric OER electrocatalysts, which will be helpful in the future manufacturing of advanced energy devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Understanding the structure-function relationships encoded on chiral catalysts is important for investigating the fundamental principles of catalytic enantioselectivity. Herein, the synthesis and self-assembly of naphthalene substituted bis - l / d -histidine amphiphiles (bis - l / d - NapHis) in DMF/water solution mixture is reported. The resulting supramolecular assemblies featuring well-defined P/M nanoribbons (NRs). With combination of the (P/M)-NR and metal ion catalytic centers (M n+ = Co2+, Cu2+, Fe3+), the (P)-NR-M n+ as chiral supramolecular catalysts show catalytic preference to 3,4-dihydroxy- S -phenylalanine (S -DOPA) oxidation while the (M)-NR-M n+ show enantioselective bias to R -DOPA oxidation. In contrast, their monomeric counterparts bis - l / d - NapHis-M n+ display an inverse and dramatically lower catalytic selectivity in the R/S -DOPA oxidation. Among them, the Co2+-coordinated supramolecular nanostructures show the highest catalytic efficiency and enantioselectivity (select factor up to 2.70), while the Fe3+-coordinated monomeric ones show nearly racemic products. Analysis of the kinetic results suggests that the synergistic effect between metal ions and the chiral supramolecular NRs can significantly regulate the enantioselective catalytic activity, while the metal ion-mediated monomeric bis - l / d - NapHis were less active. The studies on association constants and activation energies reveal the difference in catalytic efficiency and enantioselectivity resulting from the different energy barriers and binding affinities existed between the chiral molecular/supramolecular structures and R/S -DOPA enantiomers. This work clarifies the correlation between chiral molecular/supramolecular structures and enantioselective catalytic activity, shedding new light on the rational design of chiral catalysts with outstanding enantioselectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • One-step spinning for the production of hollow necklace-like carbon fiber. • CeO 2 /Co heterostructure exhibits catalytic performance and adsorption capabilities. • High surface area host material can effectively mitigate the volume expansion of sulfur. • CeO 2 /Co heterostructure facilitates the deposition and decomposition of Li 2 S. • At a current density of 2 C, the capacity decay is only 0.044 % per cycle. The shuttle effect of lithium polysulfides (LiPSs) and the sluggish reaction kinetics of LiPSs conversion pose serious challenges to the commercial feasibility of lithium-sulfur (Li-S) batteries. To address these obstacles, herein, we construct CeO 2 /Co heterostructures in hollow necklace-like carbon fibers (CeO 2 /Co-CNFs) as the cathode host material for Li-S batteries. The specific surface area of fibers is significantly enhanced by using a template, thereby promoting the utilization efficiency of sulfur. Meanwhile, CeO 2 /Co-CNFs show strong conductivity, effective adsorption to LiPSs, and robust catalytic activity for LiPSs conversion. As a result, the Li-S battery with CeO 2 /Co-CNFs displays 961 mAh g−1 at 0.2 C, with an 86 % capacity retention rate after 100 cycles. At 2.0 C current density, the composite cathode maintains an initial discharge capacity of 782 mAh g−1, with a mere 0.044 % capacity loss per cycle. Furthermore, in situations with limited electrolytes, high sulfur loading, and high areal mass loading, the composite cathode can provide a high areal capacity of 6.2 mg cm−2 over 100 cycles. This work provides a useful approach for investigating high-performance Li-S battery cathodes. [ABSTRACT FROM AUTHOR]

[Display omitted] Simultaneously enhancing the durability and catalytic performance of metal-nitrogen-carbon (M−N x −C) single–atom catalysts is critical to boost oxygen electrocatalysis for energy conversion and storage, yet it remains a grand challenge. Herein, through the combination of early and late metals, we proposed to enhance the stability and tune the catalytic activity of M−N x −C SACs in oxygen electrocatalysis by their strong interaction with the M 2 ′C–type MXene substrate. Our density functional theory (DFT) computations revealed that the strong interaction between "early-late" metal–metal bonds significantly improves thermal and electrochemical stability. Due to considerable charge transfer and shift of the d-band center, the electronic properties of these SACs can be extensively modified, thereby optimizing their adsorption strength with oxygenated intermediates and achieving eight promising bifunctional catalysts for ORR/OER with low overpotentials. More importantly, the constant-potential analysis demonstrated the excellent bifunctional activity of SACs supported on MXene substrate across a broad pH range, especially in strongly alkaline media with record-low overpotentials. Further machine learning analysis shows that the d-band center, the charge of the active site, and the work function of the formed heterojunctions are critical to revealing the ORR/OER activity origin. Our results underscore the vast potential of strong interactions between different metal species in enhancing the durability and catalytic performance of SACs. [ABSTRACT FROM AUTHOR]

[Display omitted] The industrial applications of enzymes are usually hindered by the high production cost, intricate reusability, and low stability in terms of thermal, pH, salt, and storage. Therefore, the de novo design of nanozymes that possess the enzyme mimicking biocatalytic functions sheds new light on this field. Here, we propose a facile one-pot synthesis approach to construct Cu-chelated polydopamine nanozymes (PDA-Cu NPs) that can not only catalyze the chromogenic reaction of 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP), but also present enhanced photothermal catalytic degradation for typical textile dyes. Compared with natural laccase, the designed mimic has higher affinity to the substrate of 2,4-DP with K m of 0.13 mM. Interestingly, PDA-Cu nanoparticles are stable under extreme conditions (temperature, ionic strength, storage), are reusable for 6 cycles with 97 % activity, and exhibit superior substrate universality. Furthermore, PDA-Cu nanozymes show a remarkable acceleration of the catalytic degradation of dyes, malachite green (MG) and methylene blue (MB), under near-infrared (NIR) laser irradiation. These findings offer a promising paradigm on developing novel nanozymes for biomedicine, catalysis, and environmental engineering. [ABSTRACT FROM AUTHOR]

• The stronger electronegativity of Ag in Ag/Co 3 O 4 led to richer surface Co3+. • Ag/Co 3 O 4 gained by Ag-reduction method showed higher surface Co3+/Co2+ ratio. • The reducibility of Co 3 O 4 was greatly improved by the loading of Ag via reduction method. • Ag/Co 3 O 4 prepared by Ag-reduction method showed higher catalytic activity. Silver (9 wt.%) was loaded on Co 3 O 4 -nanofiber using reduction and impregnation methods, respectively. Due to the stronger electronegativity of silver, the ratios of surface Co3+/Co2+ on Ag/Co 3 O 4 were higher than on Co 3 O 4 , which further led to more adsorbed oxygen species as a result of the charge compensation. Moreover, the introducing of silver also obviously improved the reducibility of Co 3 O 4. Hence the Ag/Co 3 O 4 showed better catalytic performance than Co 3 O 4 in benzene oxidation. Compared with the Ag/Co 3 O 4 synthesized via impregnation method, the one prepared using reduction method (named as AgCo-R) exhibited higher contents of surface Co3+ and adsorbed oxygen species, stronger reducibility, as well as more active surface lattice oxygen species. Consequently, AgCo-R showed lowest T 90 value of 183°C, admirable catalytic stability, largest normalized reaction rate of 1.36 × 10−4 mol/(h·m2) (150°C), and lowest apparent activation energy (E a) of 63.2 kJ/mol. The analyzing of in-situ DRIFTS indicated benzene molecules were successively oxidized to phenol, o-benzoquinone, small molecular intermediates, and finally to CO 2 and water on the surface of AgCo-R. At last, potential reaction pathways including five detailed steps were proposed. [ABSTRACT FROM AUTHOR]

• NTP-catalytic system improves pollutant degradation efficiency and CO 2 selectivity. • CuMnTiOx has higher activity than CeMnTiOx in the NTP-catalytic system. • Discharge determines the degradation of o-DCB and catalytic activity determines S CO2 and the degradation of O 3. • Cu doping increases the lifetime of the catalyst. In order to study the degradation process of dioxins in industrial flue gas, the decomposition of o -dichlorobenzene (o -DCB) in a DBD plasma catalytic reactor was investigated. The results showed that an NTP-catalyzed system, especially using the CuMnTiO x catalyst, had better o -DCB degradation performance compared to plasma alone. The combination of the CuMnTiO x catalyst with NTP can achieve a degradation efficiency of up to 97.2% for o -DCB; the selectivity of CO and CO 2 and the carbon balance were 40%, 45%, and 85%, respectively. The dielectric constant and electrical property results indicated that the surface discharge capacity of the catalysts played a major role in the degradation of o -DCB, and a higher dielectric constant could suppress the plasma expansion and enhance the duration of the plasma discharge per discharge cycle. According to the O1s XPS and O 2 -TPD results, the conversion of CO to CO 2 follows the M-v-K mechanism; thus, the active species on the catalyst surface play an important role. Moreover, the CuMnTiO x and NTP mixed system exhibited excellent stability, which is probably because Cu doping improved the lifetime of the catalyst. This work can provide an experimental and theoretical basis for research in the degradation of o -DCB by plasma catalyst systems. [Display omitted] [ABSTRACT FROM AUTHOR]

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Efficient and economical catalysts are pivotal for enhancing burning rate and reducing gas pollutants (e.g. NO and SO2) during coal combustion. This work evaluated the feasibility of using economical Fe3O4-based catalysts to enhance combustion rate and reduce NOx in-situ. Fe3O4 alone is found to be effective in both catalytic combustion and NO reduction, and the optimized addition is 6% based on the fuel mass. The enhancement of burning rate is mainly due to the enhanced oxygen transport with Fe3O4. Meanwhile, Fe3O4 promotes the reduction of NO with CO and coke, while CO2 and O2 in the atmosphere have adverse effect on its catalysis activity during combustion. Both CaO and CeO2 can be used to improve the efficacy of Fe3O4, and the optimal addtion was 10% CaO or 2% CeO2 together with 2% Fe3O4 for catalytic coal combustion. On the other hand, for the catalysis on NO reduction, the combination fo 2% Fe3O4-4% CaO or 2% Fe3O4-4% CeO2 could minimize the amount of NO emitted during combustion. The enhanced oxygen transfer and electron transfer are responsible for the accelerated combustion and NO reduction for the composite catalysts. [ABSTRACT FROM AUTHOR]

It is crucial to develop an acid‐free, mild, and efficient strategy for preparing 1,5‐dinitronaphthalene (1,5‐DNN) from naphthalene (NT). This work presented a one‐step NT nitration method using NO2 conjugated to an O2‐Ac2O system over Fe‐/Cu‐modified S2O82−/ZrO2 catalyst (Sα2FβCγZ). The effects of different nitration systems and Fe‐/Cu‐modified ZrO2 with various sulphur sources on NT nitration have been studied. Under optimal conditions, 99.5% of the NT conversion with 56.9% selectivity to 1,5‐DNN was obtained. Synergistic catalysis between the strong acid site and the current nitration system remarkably improved the 1,5‐DNN selectivity. The characterization results demonstrated that the appropriate Fe/Cu metals loadings combined with the covalent persulphates promoted the formation of more active tetragonal ZrO2. Chemical bonding of Zr4+ with S2O82− species allowed S6+ more electrons to withdraw than in SO42− species, which led to stronger acidity and better catalytic activity in the Sα2FβCγZ catalyst. Moreover, a plausible catalytic nitration reaction mechanism was proposed. The findings revealed that mild reaction conditions, combined with a solid superacid catalyst and NO2‐O2‐Ac2O system, offer significant advantages in reducing acid wastewater discharge and increasing target product selectivity. [ABSTRACT FROM AUTHOR]

High‐temperature CO2 electrolysis via solid oxide electrolysis cells (CO2–SOECs) has drawn special attention due to the high energy convention efficiency, fast electrode kinetics, and great potential in carbon cycling. However, the development of cathode materials with high catalytic activity and chemical stability for pure CO2 electrolysis is still a great challenge. In this work, A‐site cation deficient dual‐phase material, namely (Pr0.4Ca0.6)xFe0.8Ni0.2O3−δ (PCFN, x = 1, 0.95, and 0.9), has been designed as the fuel electrode for a pure CO2–SOEC, which presents superior electrochemical performance. Among all these compositions, (Pr0.4Ca0.6)0.95Fe0.8Ni0.2O3−δ (PCFN95) exhibited the lowest polarization resistance of 0.458 Ω cm2 at open‐circuit voltage and 800 °C. The application of PCFN95 as the cathode in a single cell yields an impressive electrolysis current density of 1.76 A cm−2 at 1.5 V and 800 °C, which is 76% higher than that of single cells with stoichiometric Pr0.4Ca0.6Fe0.8Ni0.2O3−δ (PCFN100) cathode. The effects of A‐site deficiency on materials' phase structure and physicochemical properties are also systematically investigated. Such an enhancement in electrochemical performance is attributed to the promotion of effective CO2 adsorption, as well as the improved electrode kinetics resulting from the A‐site deficiency. [ABSTRACT FROM AUTHOR]

The selective synthesis of biomimetic Fe/Mn complexes able to mimic the geometry and catalytic activity of enzymes possessing this cofactor is still a challenge. Herein, we discuss the stepwise synthesis, characterization, and magnetic properties of a Fe(II)/Mn(II) species and related Fe(II)/Fe(II) complexes. [ABSTRACT FROM AUTHOR]

A functionalized modified metal–organic framework material, T-MOF-808, was synthesized through hydrophobic modification with tetraethyl orthosilicate (TEOS) and chlorotrimethylsilane (TMCS). Then a supported oxidative desulfurization catalyst, [C12Py]3(NH4)3Mo7O24/T-MOF-808(s), was prepared by using a heteropoly acid ionic liquid as the active component. The prepared samples were characterized using FT-IR, XRD, SEM, TEM, XPS, etc. [C12Py]3(NH4)3Mo7O24/T-MOF-808(s) was used in the oxidative desulfurization of dibenzothiophene (DBT). At the same time, the effects of different loadings of the active component, oxygen sulfur ratios, reaction temperatures, and reaction time were also investigated. [C12Py]3(NH4)3Mo7O24/T-MOF-808-15%(s) could oxidize 100% of DBT in 40 min at 60 °C. Significantly, the catalyst exhibited no discernible decline in catalytic activity after 14 runs. In addition, the efficiency of sulfur removal was 85.76% in actual diesel oil. It was found that the cooperative impact of hydrophobic modification and electron transfer makes an important contribution to the high activity. The hydrophobic modification provides a novel approach for using MOF materials in the oxidative desulfurization process. [ABSTRACT FROM AUTHOR]

Development of the interfacial catalyst layer (IL) of a bipolar membrane (BPM) for its application in a water electrolyzer is carried out. Zirconium-oxide based three different metal-organic frameworks (MOFs: MOF-808, UIO-66, and Fe-MOF (dual metal)) were synthesized and separately incorporated as water-splitting IL to achieve three different BPMs. Catalytic activity of each BPM was separately evaluated and BPM with double metal clustered, Fe-based MOF (Fe-MOF) showed significantly higher water splitting performance compared to the other two containing single metal clustered (Zr) MOF. Subsequently, the catalyst loading at the interface layer was varied between 0.05, 0.2, 0.5, 1.0, and 2.0 mg∙cm−2, and BPMs with each composition were synthesized. The BPM with 1.0 mg∙cm−2 of Fe-MOF content showed the lowest (ever reported) water dissociation potential at 0.66 V, and this was ∼12% lower than the BPM without interface (synthesized inhouse). The water splitting performances along with electrochemical impedance spectroscopy (EIS) analysis were estimated and compared among three different electrode assemblies (MEAs) containing 0, 0.5, 1.0 mg∙cm−2 of Fe-MOF as interface catalyst of the single cell electrolyzer. Hydrogen production rates were separately monitored varying current density range: 0–500 mA∙cm−2, and 1.45 L∙h−1 (highest) was noted with 500 mA∙cm−2 for the MEA containing 1.0 mg∙cm−2 of Fe-MOF. This investigation is believed to be useful for designing different MOFs as IL of BPM and electrolyzers. [Display omitted] • Zirconium-oxide-based MOFs were synthesized for the interface catalyst layer in BPM. • Loading of Fe-MOF at BPM interface was optimized based on BPM I–V characteristics. • Double metal cluster Fe-MOF exhibited the lowest WD potential ever recorded, in reversed bias BPM. • Performances of single-cell BPM water electrolyzer for hydrogen production were investigated. [ABSTRACT FROM AUTHOR]

In this manuscript, we present a facile approach to synthesize a highly active catalyst for the electro-oxidation of ethanol using Pd nanoparticles supported on a Ag–Zn alloy on reduced graphene oxide. This nanocomposite material was fabricated via a two-step process of incineration followed by sol-gel synthesis. The physical properties of the catalyst were evaluated using X-ray diffraction, X-ray photoelectron spectroscopy, and scanning and transmission electron microscopies. To understand the catalyst's activity for ethanol oxidation, we performed a series of cyclic voltammetry and electrochemical impedance spectroscopy experiments in alkaline medium. The catalyst exhibited good catalytic activity with a current density of 13.01 mA cm−2, a value seven times higher than the commercial standard Pd/C catalyst and higher than any other previously reported Pd-based catalyst. The results were attributed synergistic effects between the Pd and alloy support along with the large electrochemically active surface area of the material. Taken together, these results suggest that ethanol electrocatalysts based on nanocomposites of Pd, Ag, and Zn is promising candidates for future ethanol fuel cells. • Facile strategy was used to prepare a support material and catalyst (Pd@Ag–Zn-rGO). • Synthesized Pd@Ag–Zn-rGO composite exhibited good catalytic activity towards ethanol electro-oxidation. • Pd@Ag–Zn-rGO catalyst exhibits lower charge transfer resistance (Rct) at the catalyst surface. [ABSTRACT FROM AUTHOR]

Electrocatalytic reduction of nitrate to ammonia (NO 3 RR) is one of the effective methods to treat environmental pollution caused by nitrate and to produce valuable product of ammonia at the same time. Single-atom catalysts based two-dimensional metalloporphyrin monolayers as effective catalysts for NO 3 RR is investigated in this study by first-principles calculations and interpretable machine learning. Trough high-throughput four step screening procedures, three catalysts (NbPP, TaPP and WPP) finally stood out with high stability, catalytic selectivity and activity for NH 3 production (U L = −0.24, −0.28 and −0.33 V respectively). With Δ G *NO3 and d band center as descriptors, volcano curves were construct to explain the activity trend, in which the three catalysts are just located near the top of the volcano. An effective model for the catalyst performance was built by machine learning to illustrate the possible relationship between adsorption free energy of nitrate and the intrinsic properties of the catalyst, which shows Q TM , N, χ and d TM-N have significant effect on catalyst performance. In all, this study screened effective catalyst and provides theoretical guidance for the rational design of SACs for NO 3 RR. • SACs based on 2D metalloporphyrin monolayers for NO 3 RR investigated. • Four step procedures screened NbPP, TaPP and WPP with high-performance. • Effective model for the catalyst performance built with machine learning. • Q TM , N, χ and d TM-N have significant joint effect on catalyst performance. [ABSTRACT FROM AUTHOR]

The Co-based perovskite of SrNb 0.1 Co 0.7 Fe 0.2 O 3-δ (SNCF) stands out for its high intrinsic catalytic activity toward the oxygen evolution reaction (OER) in the alkaline solution. However, the low catalytic activity of SNCF toward the oxygen reduction reaction (ORR) restricts its application in the zinc-air batteries (ZABs). To address this issue, we develop the oxygen vacancy enriched heterostructure (SNCF–NF–Co 3 O 4 @N 2) including the SNCF nanofibers with the diameter of 80 nm and Co 3 O 4 nanoparticles anchored on the SNCF surface by electrospinning and sintering in N 2. Due to the high charge/reactant transfer rate, Co3+/Co2+ ratio and oxygen vacancy concentration, SNCF-NF-Co 3 O 4 @N 2 demonstrates the superior bifunctional oxygen catalytic activity. Specially, the ORR half-wave potential can reach 0.69 V, and the OER potential at 10 mA cm−2 is as low as 1.57 V. Remarkably, the aqueous and solid-state ZABs with SNCF-NF-Co 3 O 4 @N 2 exhibit the high peak power densities of 181.2 and 73.3 mW cm−2, respectively. Furthermore, SNCF-NF-Co 3 O 4 @N 2 based ZAB demonstrates an impressive energy efficiency of 79.6%. This study introduces an innovative strategy for enhancing the bifunctional oxygen catalytic performances of Co-based perovskites. [Display omitted] • SNCF-NF-Co 3 O 4 @N 2 heterostructure is prepared by electrospinning followed by sintering in N 2. • SNCF-NF-Co 3 O 4 @N 2 has the abundant oxygen vacancies and high Co3+/Co2+ ratio. • SNCF-NF-Co 3 O 4 @N 2 demonstrates the superior ORR/OER catalytic activities and stabilities. • The ZABs with SNCF-NF-Co 3 O 4 @N 2 show the high reversibility and cycling stability. [ABSTRACT FROM AUTHOR]

Finding a catalyst for overall water splitting (OWS) with robust thermodynamic stability and optimal electronic characteristics remains a significant challenge. This study investigates the thermodynamic stability and interfacial properties of zigzag and armchair MoS 2 /WS 2 in-plane heterostructures using ab-initio molecular dynamics (AIMD) and density functional theory (DFT) simulations. The motivation behind this research is to identify highly efficient and stable catalysts for OWS. The AIMD simulations confirm the thermodynamic stability of both heterostructures under working conditions. Notably, the zigzag MoS 2 /WS 2 in-plane heterostructure demonstrates superior charge separation efficiency, with larger conduction band (0.91 eV) and valence band (0.71 eV) offsets compared to the armchair configuration. The unique chemical bonding and type-II band alignment at the zigzag junction enhance charge transfer, resulting in excellent catalytic activities with ultralow overpotentials for oxygen (0.96 V) and hydrogen (0.3 V) evolution reactions at pH = 0. Additionally, the zigzag heterostructure achieves a high solar-to-hydrogen (STH) conversion efficiency of 12.29%, making it a promising candidate for practical applications in OWS. These findings contribute to the advancement of water splitting technology and encourage further research on in-plane interface formation among diverse materials. [Display omitted] • Electronic properties and stability studied via DFT and molecular dynamics simulations. • Photocatalytic characteristics of in-plane heterostructures thoroughly examined. • Zigzag in-plane heterostructure showed excellent catalytic activity and low overpotentials. • Zigzag in-plane heterostructure has 12.29% solar-to-hydrogen conversion efficiency. [ABSTRACT FROM AUTHOR]

The catalytic efficiency of CeO2 in soot oxidation was significantly affected by its grain morphology and calcination temperature. Nanocube-shaped and nanorod-shaped CeO2 catalysts were synthesized via a hydrothermal method with different calcination temperatures. Activity tests revealed that the nanorod-shaped CeO2 exhibited superior catalytic activity compared to the nanocube-shaped catalysts at equivalent calcination temperatures. Furthermore, an inverse relationship between the catalytic activity and the calcination temperature was observed in the nanorod-shaped CeO2 catalysts, with those calcined at 300 °C exhibiting the most effective low-temperature catalytic performance. Combined characterization techniques and density functional theory calculations showed that the improved catalytic performance can be attributed to the increased abundance of oxygen vacancies, enhanced lattice oxygen mobility and higher surface energy due to their unique surface defect structure and electronic structural feature, in addition to the reduction in grain size. [ABSTRACT FROM AUTHOR]

In this study, NiTiO3 nanoparticles supported on exfoliated montmorillonite K30 (MK30) were synthesised in an eco-friendly manner using ultrasonication and were used as a benign heterogeneous catalyst for the synthesis of 4-amino pyrimidine analogues in a microwave medium. The nature of the catalyst was investigated using various characterization techniques, including XRD, FT-IR, TGA, BET, FE-SEM, TEM, and XPS. The catalytic activity of the synthesised catalyst was examined, and 20% NiTiO3/MK30 at 25 wt% showed efficient catalytic activity with high yields compared to other loadings. Non-conventional microwave irradiation was used to carry out the reaction under mild conditions, resulting in a high conversion rate. The reaction was optimised with respect to the type and amount of the catalyst, temperature, solvent, and microwave power. The scope of the reaction was extended using various aldehyde derivatives, which also produced high yields. After 6 cycles, the recovered catalyst showed good catalytic activity, achieving high yields (88–95%) within 5 min. Mechanistic investigation of the reaction hypothesized the 1st step as the synthesis of arylidene malononitrile via Knoevenagel condensation of aldehyde and di-cyanomethane, followed by the Michael addition of acetamidine to arylidene malononitrile and aromatisation to produce 2-methyl-4-amino-pyrimidine-5-carbonitriles. This synthetic approach offers several advantages, including high yield, benign reaction conditions, short reaction time, straightforward work procedure, and catalyst reusability. [ABSTRACT FROM AUTHOR]

In advanced oxidation processes (AOPs), the degradation of organic pollutants by the oxidation of reactive oxygen species (ROS) generated from the interaction between H2O2 and active species Fe2+/Fe3+ has gained significant attention. The cycle of Fe2+/Fe3+ in the catalytic oxidation plays a key role. Herein, a kind of N-doped carbon encapsulated FeMoxOy nanocrystalline material (FeMo@NC) was fabricated using a precipitation–calcination approach and applied to degrade organic pollutants in AOPs. The composite catalyst presents efficient catalytic activity for removing rhodamine B (RhB), methylene blue (MB), congo red (CR) and methyl orange (MO). The facilitating effect of Mo on the Fe2+/Fe3+ cycle and the phase structure and composition of the catalyst on the degradation was explored. Meanwhile, the recovery and reusability of the catalyst were assessed, proving its excellent stability in the degradation process. Quenching experiments demonstrate that the catalyst can activate H2O2 to generate singlet oxygen (1O2) that serves as the main ROS to degrade RhB, and the degradation pathway and mechanism are then proposed. [ABSTRACT FROM AUTHOR]

In advanced oxidation processes (AOPs), the degradation of organic pollutants by the oxidation of reactive oxygen species (ROS) generated from the interaction between H2O2 and active species Fe2+/Fe3+ has gained significant attention. The cycle of Fe2+/Fe3+ in the catalytic oxidation plays a key role. Herein, a kind of N-doped carbon encapsulated FeMoxOy nanocrystalline material (FeMo@NC) was fabricated using a precipitation–calcination approach and applied to degrade organic pollutants in AOPs. The composite catalyst presents efficient catalytic activity for removing rhodamine B (RhB), methylene blue (MB), congo red (CR) and methyl orange (MO). The facilitating effect of Mo on the Fe2+/Fe3+ cycle and the phase structure and composition of the catalyst on the degradation was explored. Meanwhile, the recovery and reusability of the catalyst were assessed, proving its excellent stability in the degradation process. Quenching experiments demonstrate that the catalyst can activate H2O2 to generate singlet oxygen (1O2) that serves as the main ROS to degrade RhB, and the degradation pathway and mechanism are then proposed. [ABSTRACT FROM AUTHOR]

Single-atom nanozymes (SAzymes) represent a cutting-edge advancement in nanomaterials, merging the high catalytic efficiency of natural enzymes with the benefits of atomic economy. Traditionally, natural enzymes exhibit high specificity and efficiency, but their stability are limited by environmental conditions and production costs. Here we show that SAzymes, with their large specific surface area and high atomic utilization, achieve superior catalytic activity. However, their high dispersibility poses stability challenges. Our review focuses on recent structural and preparative advancements aimed at enhancing the catalytic specificity and stability of SAzymes. Compared to previous nanozymes, SAzymes demonstrate significantly improved performance in biomedical applications, particularly in tumor medicine. This progress positions SAzymes as a promising tool for future cancer treatment strategies, integrating the robustness of inorganic materials with the specificity of biological systems. The development and application of SAzymes could revolutionize the field of biocatalysis, offering a stable, cost-effective alternative to natural enzymes. [ABSTRACT FROM AUTHOR]

Interstitial filling of light atoms strongly affects the electronic structure and adsorption properties of the parent catalyst due to ligand and ensemble effects. Different from the conventional doping and surface modification, constructing ordered intermetallic structures is more promising to overcome the dissolution and reconstruction of active sites through strong interactions generated by atomic periodic arrangement, achieving joint improvement in catalytic activity and stability. However, for tightly arranged metal lattices, such as iridium (Ir), obtaining ordered filling atoms and further unveiling their interstitial effects are still limited by highly activated processes. Herein, we report a high‐temperature molten salt assisted strategy to form the intermetallic Ir−B compounds (IrB1.1) with ordered filling by light boron (B) atoms. The B residing in the interstitial lattice of Ir constitutes favorable adsorption surfaces through a donor‐acceptor architecture, which has an optimal free energy uphill in rate‐determining step (RDS) of oxygen evolution reaction (OER), resulting in enhanced activity. Meanwhile, the strong coupling of Ir−B structural units suppresses the demetallation and reconstruction behavior of Ir, ensuring catalytic stability. Such B‐induced interstitial effects endow IrB1.1 with higher OER performance than commercial IrO2, which is further validated in proton exchange membrane water electrolyzers (PEMWEs). [ABSTRACT FROM AUTHOR]