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Zeolitic Imidazolate Frameworks-8 (ZIF-8) is commonly used as an ideal precursor for non-noble metal catalysts because of its high specific surface area, ultra-high porosity, and N-rich content. Upon pyrolyzing ZIF-8 at 900 °C in Ar, the resulting material, referred to as Z8, displayed good activity toward the oxygen reduction reaction (ORR). Then the ZIF-8 was mixed with various conductive carbon materials, such as multiwall carbon nanotubes (MWCNTs), Acetylene black (ACET), Vulcan XC-72R (XC-72R), and Ketjenblack EC-600JD (EC-600JD), to form Z8 composites. The Z8/MWCNTs composite exhibited enhanced ORR activity owing to its network structure, meso-/microporous hierarchical porous structure, improved electrical conductivity, and graphitization. Subsequently, iron and nitrogen co-doping is achieved through the pyrolysis of a mixture comprising Fe, N precursor, and ZIF-8/MWCNTs, which is denoted as FeN-Z8/MWCNTs. The intrinsically high electrical conductivity of MWCNTs facilitated efficient electron transfer during the ORR, while the meso-/microporous hierarchical porous structure and network structure of Fe, N co-doped ZIF-8/MWCNTs promoted oxygen transport. The presence of Fe-containing species in the catalyst acted as activity centers for ORR. This strategy of preparing Z8 composites and modifying them with Fe, N co-doping offers an insightful approach to designing cost-effective electrocatalysts. [ABSTRACT FROM AUTHOR]

Surface property modification of catalyst support is a straightforward approach to optimize the performance of supported noble metal catalysts. In particular, oxygen vacancies and hydroxyl groups play significant roles in promoting noble metal dispersion on catalysts as well as catalytic stability. In this study, we developed a nanoflower-like TiO2-supported Pd catalyst that has a higher concentration of oxygen vacancies and surface hydroxyl groups compared to that of commercial anatase and P25 support. Notably, due to the distinctive structure of the nanoflower-like TiO2, our catalyst exhibited improved dispersion and stabilization of Pd species and the formation of abundant reactive oxygen species, thereby facilitating the activation of CO and O2 molecules. As a result, the catalyst showed remarkable efficiency in catalyzing the low-temperature CO oxidation reaction with a complete CO conversion at 80 °C and stability for over 100 h. [ABSTRACT FROM AUTHOR]

The hydrogen evolution reaction (HER), as a pivotal half-reaction, significantly hinders the advancement of energy conversion efficiency. Metal electrodeposition on catalysts has been demonstrated to effectively enhance the HER reactivity. Here, Ni3S2–Fe–Ni with a multilayer structure was obtained by the electrodeposition of Ni3S2 with dopants Fe/Ni, in which a number of active sites were achieved and the intrinsic conductivity of the catalyst was well improved. Elemental analyses revealed the multilayer structure consisting of Ni3S2, NiS, and Fe. The Ni3S2–Fe–Ni catalyst exhibited impressive electrochemical performance due to optimization of its structure with the overpotentials of the HER and OER of only 83 and 190 mV. Notably, at a higher current density of 100 mA cm−2, the overpotentials for the HER and OER are only 339 and 365 mV. As a bifunctional electrocatalyst, its total splitting voltage was only 1.55 V. The catalysis performance remained nearly unchanged even after 48 h of stability testing. Finally, density functional theory (DFT) calculations revealed that the potential barriers in each reaction step of the OER are evenly distributed, and optimizing the Ni3S2 structure with iron and nickel atoms reduced the reaction energy barriers during the electrochemical process, improving the OER/HER performance. [ABSTRACT FROM AUTHOR]

Compared with heavy metal catalysts, metal-free catalysts that activate persulfate (PS) for controlling organic pollutants are more economical, environmentally friendly, and safer for human health. Utilizing ZIF-8 particles as templates and polyphosphazene as the precursor, hollow N, P, and O tri-doped carbon microspheres (NPOC) with a hierarchical pore structure were successfully synthesized from ZIF-8@polyphosphazene. Their morphology and structure were investigated by SEM, TEM, TGA, XPS, BET, and FT-IR. Otherwise, NPOC were used as catalysts to activate PS for the oxidative degradation of tetracycline. The dosage of catalyst and oxidant, tetracycline concentration, carbonization temperature, and pH can all have a substantial influence on the oxidative degradation of tetracycline. Free radical testing by EPR reveals that HO˙ and SO4˙− are generated and the radical pathway is dominant in the oxidative degradation process. NPOC exhibited superior catalytic oxidation performance and good reusability, indicating their potential for application for eliminating TC from aqueous solution. [ABSTRACT FROM AUTHOR]

Electrocatalytic water decomposition couple with renewable energy is considered as a green and sustainable method for hydrogen production. However, the development of non-precious metal bifunctional catalysts remains one of the major bottlenecks in electrochemical water decomposition, hindering the key challenges for its commercial application. In this paper, we report a simple and rapid synthesis of an iron metal-organic skeleton (Fe-MOF) precursor at room temperature via the flash nanoprecipitation (FNP) technique. The precursor reacts with SiCl 4 to derive a Si-Fe-MOF catalyst with mesoporous structure. The electrochemical performance tests reveal that compared to Fe-MOF, Si-Fe-MOF exhibits significantly better performance, with overpotentials of 181 mV and 269 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) respectively (while Fe-MOF has overpotentials of 297 mV for HER and 337 mV for OER) at a current density of 10 mA cm−2, and it possesses superior stability, respectively, at 10 mA cm−2, and has superior stability. Meanwhile, Si-Fe-MOF is used as a bifunctional catalyst with a full hydrolysis voltage of 1.62 V. It is found by in situ Raman spectroscopic characterization that Si-Fe-MOF is converted from Fe metal sites to more active FeOOH during the OER process. DFT calculations show that the doping of Si atoms in Si-Fe-MOF optimize the electronic structure of the catalyst and optimize the reactive intermediates' adsorption. • Si-doped Fe-MOF with improved electrolytic water performance. • The mesoporous structure of Si-Fe-MOF provides more active sites. • Revealing the formation of intermediate hydroxylated iron substances. • Silicon doping to optimize the adsorption energy of intermediates. • SiCl 4 enables silicon doping and promotes waste utilisation. [ABSTRACT FROM AUTHOR]

The key to designing energy-efficient hydrogen production systems lies in the development of highly catalytic, low-cost non-precious metal catalysts, along with the substitution of high-energy-consuming oxygen evolution reactions with reactions involving easily oxidizable small molecules at the anode. In this paper, molybdates (NiMoO 4 and CoMoO 4) that grow on nickel foam are treated with vulcanization and nitriding methods, and Mo doped Ni 3 S 2 (Mo–Ni 3 S 2) and N doped CoMoO 4 (N–CoMoO 4) are prepared, respectively. Mo–Ni 3 S 2 exhibits excellent UOR activity requiring only 1.335 V to drive 100 mA cm−2. It is found that Mo–Ni 3 S 2 participated in both of the decomposition of urea (15.4 %) to form NH 3 and the oxidation reaction of urea (84.6 %) to form N 2 to keep the anodic reaction in the low potential range, avoiding the oxidation of nickel sites in the catalyst to form NiOOH. In addition, N–CoMoO 4 catalyst exhibits excellent hydrogen evolution reaction (HER) activity requiring only 67 mV to drive 100 mA cm−2. Finally, the catalysts prepared by molybdate are used to construct urea oxidation electrolytic system. The Mo–Ni 3 S 2 (+) || N–CoMoO 4 (−) urea oxidation-assisted water splitting system requires only 1.47 V to achieve 100 mA cm−2, which is a voltage reduction of 180 mV compared to conventional water electrolysis systems. The system realizes high energy efficiency hydrogen production and urea wastewater purification. This work provides insights into the design of low-energy-consuming hydrogen production systems. [Display omitted] • The catalysts prepared by molybdate exhibit efficient UOR and HER activity. • Mo–Ni 3 S 2 follows a new UOR mechanism of urea decomposition and urea oxidation. • The Mo–Ni 3 S 2 (+) || N–CoMoO 4 (−) system requires only 1.47 V to afford 100 mA cm−2. • We couple UOR and HER to construct an energy-saving hydrogen production system. [ABSTRACT FROM AUTHOR]

With the aim of developing efficient non-noble metal catalysts for hydrogen evolution reaction (HER), this work synthesized a Ni–Se–Lu electrocatalyst by incorporating the rare earth element Lu to modify the Ni–Se electrode. The hydrogen evolution performance of the Ni–Se–Lu electrocatalyst under alkaline conditions was investigated on the basis of the micromorphology and structure of the electrode. In 1 M KOH solution, the Ni–Se–Lu electrode exhibited small overpotentials of 52 and 105 mV at current densities of 10 and 50 mA cm−2, respectively, along with a Tafel slope of 63.8 mV·dec−1. Electrochemical analysis results revealed increased active sites and electrochemically active surface area and improved surface roughness after the introduction of Lu element. Moreover, excellent stability in hydrogen evolution was demonstrated with a potential decay rate below 5% after 72 h of electrolysis. [Display omitted] • Ni–Se–Lu/NF electrocatalyst is developed via a facile and simple galvanostatic electrodeposition method. • Ni–Se–Lu/NF electrocatalyst showed excellent HER activity with low overpotential of 52 mV at 10 mA cm−2. • The excellent HER activity can be attributed to the increased intrinsic activity and accelerated electron transfer rate. [ABSTRACT FROM AUTHOR]

Efficient non-precious metal electrocatalysts are crucial for hydrogen production through water electrolysis. Combining a superhydrophilic electrocatalyst with oxygen vacancy and a conductive carbon matrix is significant for NiFe LDH-based oxygen evolution reaction (OER) applications. In this study, NiFe LDH nanoflowers and Co-doped NiFe LDH nanoneedles were synthesized on graphite felt through an in-situ self-assembly strategy. Further results have shown that doping Co into NiFe LDH nanoarrays significantly enhances the specific surface area and oxygen vacancy density, while the graphite felt serves as a conductive scaffold and prevents active sites detachment. Oxygen vacancies in Co 3 –Ni 7 Fe 3 LDH/TGF adjust the electronic configuration, and superhydrophilicity promotes effective electrolyte diffusion. This synergy endows Co 3 –Ni 7 Fe 3 LDH/TGF with excellent OER performance, lower overpotential of 252 mV (10 mA cm−2), a Tafel slope (63.13 mV), and stability at high current densities. This research provides a new perspective for utilizing non-precious metal catalysts on carbon substrates for hydrogen production. [Display omitted] • Co–NiFe LDH was in-situ grown on graphite felt by self-assembly strategy. • Incorporating Co increases the density of oxygen vacancies in NiFe LDH. • Nanoneedle structure boosts specific surface area and provides many active sites. • Co 3 –Ni 7 Fe 3 LDH/TGF shows a low overpotential of 252 mV at 10 mA cm−2 for OER. • Superhydrophilic Co 3 –Ni 7 Fe 3 LDH/TGF shows robust stability at high current density. [ABSTRACT FROM AUTHOR]

The construction of chiral motifs containing nonadjacent stereocenters in an enantio‐ and diastereoselective manner has long been a challenging task in synthetic chemistry, especially with respect to their stereodivergent synthesis. Herein, we describe a protocol that enables the enantio‐ and diastereoselective construction of 1,5/1,7‐nonadjacent tetrasubstituted stereocenters through a Pd/Cu‐cocatalyzed Heck cascade reaction. Notably, a C=C bond relay strategy involving the shift of the π‐allyl palladium intermediate was successfully applied in the asymmetric construction of 1,7‐nonadjacent stereocenters. The current method allows for the efficient preparation of chiral molecules bearing two privileged scaffolds, oxindoles and non‐natural α‐amino acids, with good functional group tolerance. The full complement of the four stereoisomers of products bearing 1,5/1,7‐nonadjacent stereocenters could be readily accessed by a simple combination of two chiral metal catalysts with different enantiomers. [ABSTRACT FROM AUTHOR]

Tuning the interfacial structure of metal oxide substrates is an essential strategy to induce electronic structure reconstruction of supported catalysts, which is of great importance in optimizing their catalytic activities. Herein, vanadium oxides‐supported Ir catalysts (Ir‐V2O3, Ir‐VO2, and Ir‐V2O5) with different interfacial bonding environments (Ir‐V, Ir‐Obri, and Ir‐O, respectively) were investigated for hydrogen evolution reaction (HER). The regulating mechanism of the influence of different interfacial bonding environments on HER activity was investigated by both experimental results and computational evidence. Benefiting from the unique advantages of interfacial Ir‐V direct metal bonds in Ir‐V2O3, including enhanced electron transfer and electron donation ability, an optimized HER performance can be obtained with lowest overpotentials of 16 and 26 mV at 10 mA cm−2, high mass activities of 11.24 and 6.66 A mg−1, and turnover frequency values of 11.20 and 6.63 s−1, in acidic and alkaline conditions respectively. Furthermore, the assembled Ir‐V2O3||RuO2 anion exchange membrane (AEM) electrolyzer requires only 1.92 V to achieve a high current density of 500 mA cm−2 and realizes long‐term stability. This study provides essential insights into the regulating mechanism of interfacial chemical bonding in electrocatalysts and offers a new pathway to design noble metal catalysts for different applications. [ABSTRACT FROM AUTHOR]

Metal atom catalysts have been among the most important research objects due to their specific physical and chemical properties. However, precise control of the anchoring of metal atoms is still challenging to achieve. Cobalt and iridium atomic arrays formed sequentially ordered stable arrays in graphdiyne (GDY) triangular cavities depending on their intrinsic chemical properties and interactions. The success of this method was attributed to multifunctional integration of GDY, enabling selective growth from one to several atoms and various atomic densities. The bimetallic atom arrays show several advantages resulting from reducibility of acetylene bonds, space limiting effect, incomplete charge transfer between GDY and metal atoms, and sp‐C hybridized triple bond skeleton. This well‐designed system exhibits unprecedented oxygen evolution reaction (OER) performance with a mass activity of 2.6 A mgcat.−1 at a low overpotential of 300 mV, which is 216.6 times higher than the state‐of‐the‐art IrO2 catalyst, and long‐term stability. [ABSTRACT FROM AUTHOR]

Metal ion (Mn+ ${{{\rm M}}^{{\rm n}+}}$ /oxidant) and UV light catalyzed (UV/oxidant) mineralization and biodetoxification of Ponceau Xylidine (PX) was undertaken in this study. Hydrogen peroxide (HP) and ammonium persulphate (APS) were employed as oxidants and Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ and Ag+ ${{{\rm A}{\rm g}}^{+}}$ as metal ion catalysts. Although highest mineralization in Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ /APS and UV/HP systems was exhibited at pH 1 (63.09 %) and 3 (64.83 %), respectively, lowest was shown by Ag+ ${{{\rm A}{\rm g}}^{+}}$ /oxidant systems at any pH. The Fenton process achieved mineralization of ≈48.50 % within the pH range of 3 to 6.15. The study established Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ as a better catalyst than Ag+ ${{{\rm A}{\rm g}}^{+}}$ , and HP, a better oxidant (2.5 times more effective) than APS. Mineralization with UV/HP at 120 min is highest at pH 3 (92.0 %) and 6.15 (86.17 %). Various inorganic anions were found to inhibit mineralization. The maximum and minimum inhibition was shown by Cl- ${{{\rm \ }{\rm C}{\rm l}}^{-}}$ in UV/HP and UV/APS systems respectively. The inhibition effect of NO3- ${{{\rm N}{\rm O}}_{3}^{-}}$ decreases with concentration till 0.01 mM, beyond which an increasing trend was observed. This study also demonstrates that the biodetoxification efficiency of various systems is in the order: UV/HP>UV/APS>Fe2+ ${{{\rm F}{\rm e}}^{2+}}$ /HP. Thus, UV/HP is the most suitable system for the treatment of PX, displaying a biodetoxification efficiency of 83.0 % and mineralization of 92.0 %. [ABSTRACT FROM AUTHOR]

Glycine derivatives are prevalent structural motifs that can be easily found in many bioactive molecules and natural isolates. To date, chemical synthesis of hydrazino-containing glycine derivatives has mainly focused on the utilization of metal catalysts or light-irradiation methods. Herein, we report a three-component reaction of amines, azodicarboxylates, and diazoalkanes under green and sustainable reaction conditions, leading to a wide range of hydrazino-containing glycine derivatives in good to excellent yields. Compared to the reported methods, the as-developed method does not require catalysts or light irradiation. The success of the scale-up reaction, synthetic transformation of the formed glycine products, and the direct aqueous media synthesis further rendered the method attractive and valuable. Control experiments together with detailed mechanism studies revealed that the in situ formed diaziridines are the key reaction intermediates. [ABSTRACT FROM AUTHOR]

Due to the high oxidation potential of arenes and alkenes, previous methods of benzylic and allylic C–H oxidation necessitated the use of strong oxidizing agents, metal catalysts, or free radical initiators (such as photocatalysts or hydrogen atom transfer reagents) to be effective. Herein, we employ oxygen to generate a triple-spin charge transfer state with π-conjugated compounds effectively accessing the triplet excited states of arenes, followed by energy transfer to form singlet oxygen facilitating C–H bond oxidation. Distinct from previous oxidations, it is the first time that a series of natural products and drug molecules (27 examples) are selectively oxidized without any catalysts or additives. The transformation can be implemented under sunlight to produce valuable unsaturated (aromatic) ketones and only water as waste, which meets every one of the 12 principles of green chemistry. [ABSTRACT FROM AUTHOR]

N-Substituted 5-(hydroxymethyl)-2-furfuryl amines have been obtained through the reductive amination of 5-hydroxymethylfurfural (HMF) with a variety of primary amines using a non-noble metal catalyst based on monodisperse Co nanoparticles covered by a thin carbon layer. The Co@C catalyst was highly active, selective and stable, allowing us to perform the reductive amination of HMF under very mild reaction conditions (60 °C and 4 bar H2) using ethanol as a green solvent and achieve the corresponding amino-alcohol in yields ranging from 80 to 99%. Moreover, the reaction was extended to other furanic aldehydes with excellent success. Furthermore, in order to synthesize amino-ester derivatives, precursors of ammonium salt-based surfactants, the reductive amination of HMF with methylamine was coupled with the selective esterification of the hydroxymethyl group of the furan ring with fatty acids using lipase CALB (Novozym 435) as a biocatalyst in 2-methyltetrahydrofuran as a green and enzyme compatible solvent, achieving practically total conversion to the corresponding amino-esters. The process was implemented in flow reactors by combining two consecutive fixed bed reactors, achieving a global yield of the amino-ester derivative of 85%, which was maintained over 86 h of operation. [ABSTRACT FROM AUTHOR]

To address the shortage of fossil energy, the development of affordable and efficient non-precious metal catalysts for oxygen evolution reaction (OER) from electrocatalytic water splitting is still a crucial challenge. Herein, the bimetallic NiFe metal–organic frameworks (MOFs) are synthesized by hydrothermal and electro-deposition. Benefiting from the synergistic effect of Fe and Ni, the catalyst demonstrates extraordinary activity, which exhibits favorable OER catalytic activity in 1 M KOH solution with an overpotential of 206 mV at 10 mA cm−2. Meanwhile, the obtained NiFe-NDC presents promising stability in the 20 h test at 50 mA cm−2. [ABSTRACT FROM AUTHOR]

It is key to develop novel economical and effective non-noble metal bifunctional catalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in water splitting cells. Herein, a series of novel two-dimensional (2D) ultrathin donor-acceptor Co-based metal organic framework nanoplates (U-DA-CoMOF-NPs) as bifunctional HER/OER catalysts have been designed and fabricated based on a donor-acceptor strategy. Density functional theory calculations demonstrate that the fabricated U-DA-CoMOF-NPs are fine donor-acceptor pairs having HOMO-LUMO localizations and a HOMO-LUMO gap of 2.60 eV and give the Gibbs free energy for a reasonable OER mechanism. Additionally, changes in anions can affect the physicochemical characterizations and HER/OER performance of the fabricated U-DA-CoMOF-NPs. As a result, the fabricated U-DA-CoMOF-NPs-1 using NO 3 − as an anion exhibits the optimal HER/OER performance in alkaline solution thanks to the thinnest nanoplate thickness, the largest surface area and hierarchical mesoporous structure. Moreover, a self-assembled overall water splitting cell with U-DA-CoMOF-NPs-1/NF as both cathode and anode achieves a low potential of 1.65 V and a high cycling stability at 10 mA cm−2 for at least 15 h. The present study offers an option to design and fabricate other cost-effective donor-acceptor MOF-based catalysts for water splitting cells. • A series of U-DA-CoMOF-NPs have been fabricated with a donor-acceptor strategy. • The HOMO positioning is on Tdc, LUMO localization is at Tpt and a gap is 2.6 eV. • Co–N has more positive catalytic ability for OER than pyridinic-N and thiophene-S. • The representative U-DA-CoMOF-NPs-1 exhibits the optimal HER/OER performance. • A U-DA-CoMOF-NPs-1/NF cell shows a low potential and high stability at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Developing stable, highly active, and economical non-precious metal catalysts for the oxygen evolution reaction (OER) has been highly demanded in the new energy field since it can meet the industrial demands of large-scale electrocatalytic water splitting. A novel FeP/Ni 2 P/Fe 0.64 Ni 0.36 /C (FeNiP–FeNi–C) nanofiber was prepared by electrospinning and high-temperature phosphating. Notably, the good dispersion of FeP, Ni 2 P, and FeNi alloy nanoparticles in the nanocarbon fiber greatly increased the number of electroactive sites, and the synergistic effect between the FeP/Ni 2 P heterogeneous interface and FeNi alloy significantly improved the inherent activity of each site. Moreover, the carbon nanofibers enhanced the long-term durability of the catalyst by preventing the corrosion of the FeP, Ni 2 P, and FeNi alloy particles. Therefore, the optimal FeNiP–FeNi–C catalyst revealed exceptionally high OER activity, with overpotentials of 364 mV and 236 mV at 50 mA cm−2 and 10 mA cm−2 respectively, and the slope of Tafel of 61.00 mV·dec−1. This catalyst performs significantly better than commercial RuO 2 catalysts in alkaline electrolytes. The results of this study offer a novel perspective for the mass production of non-precious metal OER high-efficiency electrocatalysts. [Display omitted] • Novel FeNiP–FeNi–C nanofiber. • Facile and highly efficient synthesis method based on electrospinning. • High efficient electrocatalyst for oxygen evolution in water splitting. • Mechanism for improved electrocatalytic activity. [ABSTRACT FROM AUTHOR]

The electronic structure of molybdenum carbide closely resembles that of Pt, making it a promising candidate material for replacing noble metal catalysts. However, the primary challenge is the controlled and eco-friendly synthesis of molybdenum carbide. Herein, we developed a sustainable and controlled method for synthesizing a heterostructure catalyst for the electrocatalytic hydrogen evolution reaction (HER) using starch as the raw material. Through a hydrothermal redox reaction and subsequent temperature-programmed treatment under an inert atmosphere, the hexagonal Mo 2 C-cubic MoC heterostructure nanoparticles were dispersed on a carbon matrix. Our investigation into the synthesis process extensively covered the growth of MoO 2 nanocrystals and hydrochar during the hydrothermal redox reaction, as well as the phase evolution during the subsequent temperature-programmed treatment. Electrochemical assessments demonstrated the catalyst's remarkable efficiency for the hydrogen evolution reaction across both acidic and alkaline media, achieving a current density of 10 mA/cm2 with an overpotential of 139.4 mV in 1 M KOH solution and 160.7 mV in 0.5 M H 2 SO 4 solution. Combining a series of electrochemical characterizations and applying the distribution of relaxation times (DRT) analysis to operando electrochemical impedance spectroscopy (EIS) data, the superior kinetic performance of the Mo 2 C–MoC/C was demonstrated, outperforming that of single-phase molybdenum carbide. Furthermore, the catalyst has demonstrated remarkable stability even at high current densities in both acidic and alkaline electrolytes, underscoring its potential as a cathode catalyst in both alkaline water electrolyzers and proton exchange membrane (PEM) electrolyzers. Hexagonal Mo 2 C-cubic MoC heterostructure is fabricated as a high performance electrocatalyst for hydrogen evolution. This work underscores the significance of the precise synthesis of multi-phase catalysts. [Display omitted] • Starch-derived nanoscale molybdenum carbide heterostructure. • Systematic study of the synthesis process of the catalyst. • Excellent catalytic activity and stability under acidic and alkaline media. • DRT analysis visually reveals the catalyst's superior HER kinetics. [ABSTRACT FROM AUTHOR]

Enhancing the hydrolysis reaction of NaBH 4 for efficient hydrogen production requires the development of effective catalysts. In this study, the solution particles used for nanoparticles synthesized using the ultrasonic spray (US) method were produced for the first time in N 2 at room temperature in the gas and liquid intermediate phases. It also brings a new approach to synthesizing low-cost and efficient catalysts using ultrasonic spray technology. The proposed method involves US the CoCl 2 solution into the NaBH 4 solution to reduce cobalt, producing catalysts for hydrogenation. This innovative approach pioneers a gas-liquid interface reaction for metal reduction. The resulting catalysts were characterized using SEM, XRD, XPS, TEM, BET and FT-IR analysis. The influence of NaOH/NaBH 4 concentration, solution temperature, and catalyst amount on hydrogen production rate was investigated, and kinetic parameters were analyzed to understand the reaction kinetics better. The hydrogen production rates of US-Co and reduction method (RM) Co catalysts under the same conditions were calculated as 3995 ml H2 /min.g cat and 1245 ml H2 /min.g cat , respectively. The activation energy values calculated for the NaBH 4 hydrolysis of the US-Co catalyst using the nth-order and Langmuir-Hinshelwood kinetic models are 46.75 kJ/mol and 46.87 kJ/mol, respectively. Therefore, it can be concluded that the Langmuir-Hinshelwood kinetic model is consistent with the nth-order kinetic model. Experimental results showed that the ultrasonic spray method is very effective in producing active metal catalysts, offering promising opportunities for catalytic advances. [Display omitted] • A novel method of ultrasonic spray was improved for Co NPs pioneering a gas and liquid interface reaction. • The US-Co is highly active for NaBH 4 with an H 2 production rate of 3995 ml H2 /min.g cat at 30 °C. • The activation energy was calculated to be 46.75 kJ/mol with US-Co NPs. [ABSTRACT FROM AUTHOR]

Introducing interstitial light atoms shows great potential in improving the intrinsic activity and stability of metal catalysts owing to strongly affecting the electronic structure and adsorption properties. However, filling atomically dispersed light atoms into metal lattices and further unveiling their interstitial effects are still limited by tightly arranged metal lattices. Herein, the study reports a calcination reduction assisted trace light atoms filling strategy to form a series of interstitial light single atoms filled Co‐based catalysts (Co‐X@NF, X = P, N and NF = nickel foam), therefore constructing monometallic atomic interfaces between P‐coordinated Coδ+ and Co0 to promote alkaline hydrogen evolution reaction (HER). Noteworthy, the optimal Co‐P0.43@NF with rich monometallic atomic interfacial structure shows very high turnover frequency values (5.64 s−1), which is close to noble metal level and far exceeds non‐noble metal catalysts. Meanwhile, it maintains excellent stability of 150 h at 100 mA cm−2. Theoretical studies prove that P‐coordinated Coδ+ promotes H2O dissociation and Co0 optimizes H* adsorption energy, thus forming highly active monometallic atomic interfaces, which greatly accelerates the alkaline HER kinetics. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An alkyl radical initiated cyclization/tandem reaction of alkyl bromides and alkyl electrophiles by using potassium metabisulphite (K2S2O5) as a connector is developed for the synthesis of various lactam‐substituted alkyl sulfones. Notably, this process does not require a metal catalyst or metal powder reductant, highlighting its environmentally friendly features. The reaction demonstrates outstanding substrate adaptability and a high tolerance towards diverse functional groups. Furthermore, the biologically active molecules and commercially available drugs with a late‐stage modification are also highly compatible with this transformation. Mechanistic studies revealed that the reaction proceeds through a single‐step process involving intramolecular radical cyclization, "SO2" insertion, and external alkyl incorporation. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An efficient electrochemical approach has been developed for the construction of 3‐sulfanylquinoline derivatives by treating phenylethynylbenzoxazinanones with disulfides in an undivided cell. The protocol provided a convenient route to functionalized quinolines with good functional group tolerance. Moreover, it does not require any metal catalysts or additives, furnishing a series of biological quinolines in moderate to good yields. [ABSTRACT FROM AUTHOR]

The nanoconfinement approach for constructing ultra‐small nanoparticles has been effectively utilized in the development of non‐precious metal catalysts. Herein, the catalyst precursor was prepared by host‐guest assembly method, using PCN‐222 as the host and 1,1′‐bis(diphenylphosphino) ferrocene (DPPF) as the guest. After calcination, the sub‐2 nm iron oxide nanoparticles within a phosphorus‐nitrogen co‐doped carbon matrix (Fe3O4@P/N‐CDCM) was obtained. Benefiting from the nanoconfinement effect, the sub‐2 nm Fe3O4 nanoparticles were uniformly dispersed on the P/N‐CDCM matrix. As a representative application, Fe3O4@P/N‐CDCM‐600 showed remarkable catalytic activity in the reduction of various nitroaromatic compounds. Under ambient conditions, the efficient reduction of nitro compounds in aqueous solution led to excellent conversion rates (96–99 %) and selectivity (99 %) within 45 minutes. Additionally, the catalyst maintained high efficiency over 5 cycles without experiencing a noticeable decrease in activity. This work provides an innovative and cost‐effective strategy for fabricating highly dispersed non‐precious metal nanoparticles. [ABSTRACT FROM AUTHOR]

The selective conversion of unsaturated compounds has emerged as a crucial method in chemical synthesis, enabling the synthesis of functional organic molecules. In recent decades, transition metal‐catalyzed hydrosilylation has emerged as a highly successful exemplar of industrialization within the realm of organic chemistry for the production of organosilanes, which have a pivotal role in organic chemistry and materials science. Precious metal complexes are typically employed as catalysts in most industrial hydrosilylation processes. The exploration of Earth‐abundant alternatives has emerged as a focal point of considerable research attention due to the high cost, poor selectivity, and many side reactions reported for precious metal catalysts. Ligand skeleton construction, selectivity, and mechanism research are areas where cobalt catalysts have more potential than iron and nickel. This review discusses the recent advances in cobalt‐catalyzed hydrosilylation across carbon‐carbon, carbon‐oxygen, and carbon‐nitrogen multiple bonds from 2019 to 2023. [ABSTRACT FROM AUTHOR]

Green and sustainable energy alternatives to replace fossil fuels are a topic of research in scientific community, thus yielding pursuit of advancing renewable energy systems with hydrogen emerging as a suitable and viable alternative. Efficient and non‐precious metal catalysts are crucial for large‐scale electrochemical water splitting yielding clean H2. Here, a novel two‐step hydrothermal synthesis approach to fabricate manganese–cobalt selenide nano‐cubes grown directly on nickel foam (NF) (MnCo2Se4/NF) is adopted. Leveraging its hierarchically structured architecture, augmented active sites, and electrochemically active surface area, MnCo2Se4/NF material demonstrates exceptional electrocatalytic performance for both water oxidation and reduction. With an overpotential of 233 mV for oxygen evolution reaction (OER) and 187 mV for hydrogen evolution reaction at a current density of 10 mA/cm2, MnCo2Se4/NF also exhibits a Tafel slope of 44 mV/dec for sluggish OER process. Notably, this nanocrystalline catalyst displays enhanced catalytic activity under alkaline conditions, accelerates water dissociation, and maintains good stability over 50 h. Outperforming state‐of‐the‐art RuO2, particularly in two‐electrode assemblies with an overpotential of 218 mV at 10 mA/cm2, this work offers a promising pathway for designing and manufacturing of innovative bifunctional electrocatalysts for efficient water splitting processes, thereby contributing to broader goal of sustainable energy production. [ABSTRACT FROM AUTHOR]

Plastic pollution is an emerging global threat due to lack of effective methods for transforming waste plastics into useful resources. Here, we demonstrate a direct oxidative upcycling of polyethylene into high‐value and high‐volume saturated dicarboxylic acids in high carbon yield of 85.9 % in which the carbon yield of long chain dicarboxylic (C10‐C20) acids can reach 58.9% over cobalt‐doped MCM‐41 molecular sieves, in the absence of any solvent or precious metal catalyst. The distribution of the dicarboxylic acids can be controllably adjusted from short‐chain (C4‐C10) to long‐chain ones (C10‐C20) through changing cobalt loading of MCM‐41 under nanoconfinement. Highly and sparsely dispersed cobalt along with confined space of mesoporous structure enables complete degradation of polyethylene and high selectivity of dicarboxylic acid in mild condition. So far, this is the first report on highly selective one‐step preparation of long chain dicarboxylic acids. The approach provides an attractive solution to tackle plastic pollution and a promising alternative route to long chain diacids. [ABSTRACT FROM AUTHOR]

Metal phosphides have been hailed as potential replacements for scarce noble metal catalysts in many aspects of the hydrogen economy from hydrogen evolution to selective hydrogenation reactions. But the need for dangerous and costly phosphorus precursors, limited support dispersion, and low stability of the metal phosphide surface toward oxidation substantially lower the appeal and performance of metal phosphides in catalysis. We show here that a 1‐step procedure that relies on safe and cheap precursors can furnish an air‐stable Ni2P/Al2O3 catalyst containing 3.2 nm nanoparticles. Ni2P/Al2O3 1‐step is kinetically competitive with the palladium‐based Lindlar catalyst in selective hydrogenation catalysis, and a loading corresponding to 4 ppm Ni was sufficient to convert 0.1 mol alkyne. The 1‐step synthetic procedure alters the surface ligand speciation of Ni2P/Al2O3, which protects the nanoparticle surface from oxidation, and ensures that 85 % of the initial catalytic activity was retained after the catalyst was stored under air for 1.5 years. Preparation of Ni2P on a variety of supports (silica, TiO2, SBA‐15, ZrO2, C and HAP) as well as Co2P/Al2O3, Co2P/TiO2 and bimetallic NiCoP/TiO2 demonstrates the generality with which supported metal phosphides can be accessed in a safe and straightforward fashion with small sizes and high dispersion. [ABSTRACT FROM AUTHOR]

Catalytic methods to couple alcohol and alkene feedstocks are highly valuable in synthetic chemistry. The direct oxidative coupling of primary alcohols and alkenes offers a streamlined approach to ketone synthesis. Currently, available methods are based on transition metal-catalyzed alkene hydroacylation, which involves the generation of an electrophilic aldehyde intermediate from primary alcohol dehydrogenation. These methods generally require high reaction temperatures and a high loading of precious metal catalysts and are predominantly effective for branch-selective reactions with electron-rich alkenes. Herein, we designed a dual photo/cobalt-catalytic method to manipulate the reactivity of nucleophilic ketyl radicals for the synthesis of ketones from primary alcohols and alkenes in complementary reactivity and selectivity. This protocol exhibits exceptional scope across both primary alcohols and alkenes with high chemo- and regio-selectivity under mild reaction conditions. Mechanism investigations reveal the essential role of cobalt catalysis in enabling efficient catalysis and broad substrate scope. Catalytic methods to couple alcohol and alkene feedstocks are highly valuable in synthetic chemistry but available methods typically rely on transition metal-catalyzed alkene hydroacylation. Here the authors design a dual photo/cobalt-catalytic method to manipulate the reactivity of nucleophilic ketyl radicals for the synthesis of ketones from primary alcohols and alkenes in complementary reactivity and selectivity. [ABSTRACT FROM AUTHOR]

Non‐precious metal‐based nitrogen‐doped carbon (M‐Nx/C) shows great potential as a substitute for precious metal Pt‐based catalysts. However, the conventional pyrolytic methods for forming M‐Nx/C active sites are prone to issues such as the lack of synergistic interactions among bimetallic atoms and the potential encasement of active sites, leading to compromised catalytic efficiency and hindered mass transfer. In this work, a highly active FeCo‐N‐C@U‐AC electrocatalyst is developed with a high density of active sites, adequate exposure of catalytic sites, and robust mass transfer capability using the chemical vapor‐phase deposition (CVD) technique. The resulting catalyst demonstrates impressive oxygen reduction reaction (ORR) catalytic performance and stability, with half‐wave potentials of 0.820 V (0.1 M HClO4) and 0.911 V (0.1 M KOH), respectively. It also exhibits significantly enhanced stability, retaining 93.25% and 98.38% of current after continuous 50 000 s of durability testing, surpassing the retention rates of Pt/C (80.31% in HClO4 and 84.96% in KOH electrolytes). Notably, when employed as a cathode catalyst in proton exchange membrane fuel cells (PEMFCs) and zinc‐air flow batteries (ZAFBs), the FeCo‐N‐C@U‐AC catalyst delivers peak power densities of 859 and 162 mW·cm−2, respectively, showcasing competitive performance comparable to benchmark Pt/C. [ABSTRACT FROM AUTHOR]

A green, efficient and highly regioselective synthesis of flavonoids and their derivatives from β-phenoxyl ynones using wet 1,3-propanediol as reaction medium was developed, without any metal catalysts, bases, acids or additives. The reaction shows a high level of functional tolerance and a broad substrate scope, with simple operation and high atomic economy. Furthermore, a mechanism study has shown that 1,3-propanediol acts both as a participant and solvent to achieve regioselective cyclization and carbonyl site oxygen migration. Significantly, the total synthesis of drug molecules efloxate 6 and flavodilol 7 and bioactive molecules, such as 8 and MN-64, further demonstrates the efficacy and synthetic potential of this method. Moreover, most established flavonoid derivatives are found to have strong anti-inflammatory activities, during which 2d exhibits a better result with lower IC50 value of 5.67 μg mL−1. [ABSTRACT FROM AUTHOR]

Photocatalytic ammonia production holds immense promise as an environmentally sustainable approach to nitrogen fixation. In this study, In2O3/In2S3-ZnCdS ternary heterostructures were successfully constructed through an innovative in situ anion exchange process, coupled with a low-temperature hydrothermal method for ZnCdS (ZCS) incorporation. The resulting In2O3/In2S3-ZCS photocatalyst was proved to be highly efficient in converting N2 to NH3 under mild conditions, eliminating the need for sacrificial agents or precious metal catalysts. Notably, the NH4+ yield of In2O3/In2S3-0.5ZCS reached a significant level of 71.2 μmol g−1 h−1, which was 10.47 times higher than that of In2O3 (6.8 μmol g−1 h−1) and 3.22 times higher than that of In2O3/In2S3 (22.1 μmol g−1 h−1). This outstanding performance can be attributed to the ternary heterojunction configuration, which significantly extends the lifetime of photogenerated carriers and enhances the spatial separation of electrons and holes. The synergistic interplay between CdZnS, In2S3, and In2O3 in the heterojunction facilitates electron transport, thereby boosting the rate of the photocatalytic nitrogen fixation reaction. Our study not only validates the efficacy of ternary heterojunctions in photocatalytic nitrogen fixation but also offers valuable insights for the design and construction of such catalysts for future applications. [ABSTRACT FROM AUTHOR]

Two novel complexes were synthesized by the reaction of benzothiazol‐pyrimidin‐2‐ylidene ligand (BTP) with Pd (II) and Fe (III) ions. A variety of various spectral and analytical methods (infrared, 1H/NMR, 13C/NMR, electronic spectra, CHN analyses, mass spectra, thermogravimetric analysis, and magnetic susceptibility) were used to characterize the investigated BTP ligand and its complexes. Correlation of experimental results with density functional theory calculation proves that the geometry of BTP‐Fe complex is octahedral, whereas BTP‐Pd complex is square planner. The catalytic effectiveness of BTP complexes were tested for three‐component condensation process under moderate and environmentally friendly reaction conditions. Moreover, the effects of different Lewis acid, basic, and ionic liquid catalysts, as well as solvent and catalyst dose on the catalytic reaction were investigated. Both catalysts demonstrated strong catalytic capability in the carefully regulated ideal reaction circumstances. Heterogeneous catalyst BTP‐Pd exhibited superior catalytic performance compared to homogeneous catalyst BTP‐Fe. All products were obtained in high TOF (turnover frequency) numbers in the presence of these catalysts, which indicate the high efficiency of these catalysts in the synthesis of dihydro‐7H‐5‐thia‐hexaaza‐s‐indacen‐6‐one derivatives. Moreover, the two catalysts' recycling and reusability in reactions were also investigated. Heterogeneous BTP‐Pd catalyst could be reused up to seven times with high efficiency, but the homogeneous catalyst (BTP‐Fe) could only be recycled up to four times. Furthermore, the mechanism of catalytic reaction was suggested and supported by DFT calculation. The simplicity, safety, stability, use of commercially available catalysts, quick reaction times, and excellent yields make it promising for future industrial use. [ABSTRACT FROM AUTHOR]

Anion‐exchange membrane fuel cells provide the possibility to use platinum group metal‐free catalysts, but the anodic hydrogen oxidation reaction (HOR) suffers from sluggish kinetics and its source is still debated. Here, over nickel‐tungsten (Ni−W) alloy catalysts, we show that the Ni : W ratio greatly governs the HOR performance in alkaline electrolyte. Experimental and theoretical studies unravel that alloying with W can tune the unpaired electrons in Ni, tailoring the potential of zero charge and the catalytic surface to favor hydroxyl adsorption (OHad). The OHad species coordinately interact with potassium (K+) ions, which break the K+ solvation sheath to leave free water molecules, yielding an improved connectivity of hydrogen‐bond networks. Consequently, the optimal Ni17W3 alloy exhibits alkaline HOR activity superior to the state‐of‐the‐art platinum on carbon (Pt/C) catalyst and operates steadily with negligible decay after 10,000 cycles. Our findings offer new understandings of alloyed HOR catalysts and will guide rational design of next‐generation catalysts for fuel cells. [ABSTRACT FROM AUTHOR]

The utilization of single-atom catalysts (SACs) in the context of the Hydrogen Evolution Reaction (HER) holds significant promise for advancing electrocatalysis. Upon implantation or anchoring on two-dimensional (2D) materials, these catalysts exhibit improved stability, selectivity, and reactivity. This study uses density functional theory-based computational techniques to demonstrate the potential of SACs embedded on novel 2D materials, such as MBenes. To assess their HER activity, the transition metals (TMs) are screened as SACs embedded in Ti 2 B monolayer. Our results indicate that the inclusion of a single TM can finely adjust hydrogen adsorption, resulting in a characteristic volcano-like pattern, and particularly Pd-Ti 2 B emerges as a standout candidate, with an optimal Gibbs free energy of −0.057 eV. Moreover, Pd-Ti 2 B exhibits a notable exchange current density of 1.25 × 10−4 Acm−2 surpassing that of numerous traditional metal catalysts, including Pt(111), by approximately 105%. Furthermore, we underscore the electronic characteristics contributing to the extraordinary electrocatalytic activity of a single TM atom encased in Ti 2 B, viz., Pd-Ti 2 B, for HER. This study contributes greatly to our understanding of electrocatalytic processes and facilitates the development of potent MBenes-based catalysts for hydrogen evolution. [Display omitted] • SACs on 2D materials, like MBenes, hold great potential for advancing electrocatalysis. • Computational techniques demonstrate the potential of SACs embedded on novel Ti 2 B MBenes. • The TMs form strong bonds with MBene via p-d hybridization. • Pd-Ti 2 B excels for HER with near-zero Δ G H , showcasing outstanding performance. • Pd-Ti 2 B shows exceptional exchange current density, surpassing traditional metal catalysts significantly. [ABSTRACT FROM AUTHOR]

Graphene is a perfect 2D crystal of covalently bonded carbon atoms and constitutes the building block for all graphitic structures. Its superior properties make it an attractive material for a variety of technological applications. However, mass production does not meet the initial expectations. Chemical Vapor Deposition (CVD) is currently the only available method for large‐scale automated production, but the produced graphene sheets suffer from structural and morphological defects that degrade considerably the mechanical and other physical properties of synthesized graphene. Recently, the use of liquid metal catalysts (LMCat) has been proposed as an alternative platform for facile and high‐quality synthesis of single‐crystal graphene. Herein, simultaneous Raman spectroscopy combined with mechanical testing is adopted confirming that the reinforcing efficiency of the LMCat graphene is greatly improved. In fact, the effective Young's modulus of LMCat graphene has been found ≈630 GPa, which is significantly higher than the graphene grown on solid Cu substrate due to differences in the morphology of Cu substrate. Overall, this work paves the way for the development of defect‐free graphene of quality comparable to exfoliated flakes, and this will have a major technological impact for many applications. [ABSTRACT FROM AUTHOR]

To explore advanced oxidation catalysts, peroxymonosulfate (PMS) activation by Co-Ni-Mo/carbon nanotube (CNT) composite catalysts was investigated. A compound of NiCo2S4, MoS2, and CNTs was successfully prepared using a simple one-pot hydrothermal method. The results revealed that the activation of PMS by Co-Ni-Mo/CNT yielded an exceptional Rhodamine B decolorization efficiency of 99% within 20 min for the Rhodamine B solution. The degradation rate of Co-Ni-Mo/CNT was 4.5 times higher than that of Ni-Mo/CNT or Co-Mo/CNT, and 1.9 times as much than that of Co-Ni/CNT. Additionally, radical quenching experiments revealed that the principal active groups were 1O2, surface-bound SO4•−, and •OH radicals. Furthermore, the catalyst exhibited low metal ion leaching and favorable stability. Mechanism studies revealed that Mo4+ on the surface of MoS2 participated in the oxidation of PMS and the transformation of Co3+/Co2+ and Ni3+/Ni2+. The synergism between MoS2 and NiCo2S4 reduces the charge transfer resistance between the catalyst and solution interface, thus accelerating the reaction rate. Interconnected structures composed of metal sulfides and CNTs can also enhance the electron transfer process and afford sufficient active reaction sites. Our work provides a further understanding of the design of multi-metal sulfides for wastewater treatment. [ABSTRACT FROM AUTHOR]

An efficient and operationally simple method for the synthesis of β-keto sulfones through the BF3·OEt2-promoted reaction of alkynes and sodium sulfinates is developed. With its facile and selective access to the targets, it features good functional group compatibility, mild conditions, easily available starting materials, and good yields. Notably, the reaction does not require metal catalysts or chemical reagents with pungent odors. [ABSTRACT FROM AUTHOR]

Porous carbon supported metal catalyst with embedded structure has witnessed the success in enhancing catalyst stability; however, the development of a simple yet efficient strategy to fabricate catalyst with controllable embedding degree is still a great challenge. Herein, we report a facile impregnation-coating-pyrolysis (ICP) strategy to fabricate ultrafine Ru nanoparticles embedded into N-doped porous carbon nanosheets (Ru@CN). Both the dispersion and exposure degree of Ru nanoparticles in Ru@CN catalyst could be efficient controlled through regulating the coating time of carbon precursors. As expected, the obtained Ru@CN catalyst exhibited an acid resistance for the hydrogenation of levulinic acid in an aqueous phase. Specifically, the spent Ru@CN catalyst shows a significant enhancement in catalytic activity compared with fresh one because the fact that part of Ru active sites confined inside carbon support could be liberated during the reaction process. We anticipate that this ICP strategy may provide a new approach to fabricate the embedded catalyst with high hydrothermal stability. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction (OER) plays a vital role in electrolytic water splitting. It is urgent to explore highly active non-precious metal OER catalysts. Herein, the etching combined with the electrodeposition was used to synthesize the efficient Ni–Fe/p-CoAl catalyst, which exhibits ideal OER performance. A low overpotential of 282 mV and 296 mV are needed to achieve the current density of 50 mA/cm2 and 100 mA/cm2 in 1 M KOH, respectively. Moreover, the as-prepared catalyst shows good durability with no detectable degradation during long-term operation. The enhanced OER performance can be attributed to the large electrochemical surface area and the strong interaction between Ni–Fe nanosheets and active substrate. Etching combined with the electrodeposition method was used to synthesize an efficient Ni–Fe/p-CoAl catalyst for OER. [ABSTRACT FROM AUTHOR]

The essential role of metal–support interaction in ammonia synthesis was investigated by using a Pr6O11 supported Ru nanoparticles (NPs) catalyst system. Loading of Ru NPs onto the Pr6O11 support with relatively low surface area yields similar metal dispersion with respect to conventional SiO2 support. The Ru NPs on the Pr6O11 was found to exhibit excellent catalytic performance in ammonia synthesis, superior to free-standing Ru NPs and Ru NPs on conventional SiO2 support. Detailed structure analysis results reveal that the superior activity of Ru/Pr6O11 can be attributed to the enhanced interaction between the Ru NPs and Pr6O11, which can modulate the electronic structure of Ru NPs and trigger catalytic ammonia synthesis over Ru NPs on Pr6O11. Furthermore, nitrogen isotope exchange experiment reveals that superior nitrogen dissociation ability is essential for the excellent activity and intrinsic activity of Ru/Pr6O11 in ammonia synthesis. These findings demonstrate that Pr6O11 can be used as a new kind of support for preparation of efficient Ru-based catalysts for ammonia synthesis, and also open up opportunities for design of Pr6O11 supported metal catalysts for other catalytic reactions. Interaction between the Ru NPs and Pr6O11 can modulate the electronic structure of Ru NPs and trigger catalytic ammonia synthesis over Ru NPs on Pr6O11. [ABSTRACT FROM AUTHOR]

Hybrid poly‐ion complexes were synthesized through the complexation of a double hydrophilic copolymer with Ce(III) ions. These colloids act as reservoirs for cerium ions, enabling the synthesis of cerium‐based Prussian blue nanoparticles with a cubic structure, a narrow size distribution around 100 nm, and good colloidal stability in water. Upon high‐temperature calcination, these nanoparticles are transformed into a cerium/iron‐based metal oxide catalyst (CeO2/Fe2O3). The resultant composite catalyst demonstrates superior performance in the photo‐Fenton oxidation of methylene blue pollutants, achieving a conversion efficiency that rivals other metal‐based oxides and cerium‐based catalysts. [ABSTRACT FROM AUTHOR]

Hydroperoxides are key constituents of two-component dental materials. The objective of this study was to evaluate the influence of the hydroperoxide structure on the reactivity and on the mechanical properties of self-cure composites. Hydroperoxides HP1–3 were synthesized by selective catalytic oxidation of the corresponding para -substituted cumene precursors and isolated in high purity. They were characterized by 1H NMR and 13C NMR spectroscopy. 16 self-cure composites, based on the redox initiator system hydroperoxide (Cumene hydroperoxide (CHP), HP1–3 or tert.-Amyl hydroperoxide (TAH))/polymerizable thiourea ATU1 /copper(II) acetylacetonate, were formulated in Sulzer Mixpac two-component syringes. An equimolar hydroperoxide/ ATU1 ratio was selected for each self-cure composite. The reactivity and the final double-bond conversions obtained with these two-component materials was assessed using RT-FTIR spectroscopy. The flexural strength and modulus were measured using a three-point bending setup, after storage of the specimens for 45 min at 37 °C (dry) and for 24 h in water at 37 °C. The working time of each self-cure composite was measured using an oscillating rheometer. CHP derivatives bearing an electron withdrawing group (HP2 : ester or HP3 : nitrile) in the para position were found to be more reactive than CHP, whereas the compound bearing an electron donating group (tert -butyl, HP1) was less reactive; molecular modelling data were reported for a better understanding of this structure/reactivity/efficiency relationship. All CHP derivatives were more reactive than the aliphatic hydroperoxide TAH. Excellent mechanical properties were obtained with self-cure composites containing either CHP or a para -functionalized CHP derivative. By carefully selecting the amounts of oxidizing/reducing agents and metal catalyst, suitable working times can be obtained with all evaluated hydroperoxides. HP3 , thanks to its high reactivity, is nonetheless the most promising compound. The curing rate of self-cure composites can be adapted by modifying the structure of the hydroperoxide. In agreement with molecular modelling data, the incorporation of CHP derivatives bearing an electron withdrawing group in the para position is particularly attractive. Indeed, due to a significant reactivity enhancement, the desired properties (working time, flexural strength/modulus) can be obtained by incorporating moderate amounts of hydroperoxide/acylthiourea as well as particularly low contents of metal catalyst to the two-component dental materials. • Three cumene hydroperoxide derivatives were synthesized. • Self-cure composites based on various hydroperoxides were formulated and evaluated. • Excellent mechanical properties were obtained with the new hydroperoxides. • The nature of the hydroperoxide had a strong influence on the curing kinetics. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Axially chiral biaryls represent the most important class of atropisomers, and they widely exist in natural products and biologically active molecules. They also constitute a unique scaffold for chiral ligands and catalysts in organic synthesis. The development of synthetic methods to obtain such chiral compounds has received widespread attention, among which catalytically atroposelective ring‐opening of configurationally labile compounds represents one of the most attractive strategies. Various substrates with strained cyclic structures, such as the renowned Bringmann's lactones, can undergo asymmetric transformation into stable atropisomers. Known advancement primarily relies on metal catalyst combined with well‐designed chiral ligands, the approaches utilizing organocatalysis as a critical resolution strategy are notably scarce. In this study, we disclosed a N‐heterocyclic carbene (NHC)‐catalyzed asymmetric ring‐opening reaction of biaryl lactams via direct atroposelective nucleophilic activation. The optimized bulky carbene catalyst ensures that the reaction can proceed under mild conditions, affording the desired product with good to excellent yields and atroposelectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] Owing to the high cost of precious metal catalysts for the oxygen evolution reaction (OER), the production of highly efficient and affordable electrocatalysts is important for generating pollution-free and renewable energy via electrochemical processes. A facile hydrothermal approach was employed to synthesize hybrid mesoporous iron-nickel bimetallic sulfides @ P, N -doped carbon for the OER. The prepared Fe 0.5 NiS 2 @C exhibited an overpotential (η) of 250 mV at 10 mA/cm2. This exceeded the overpotentials recently reported for surface-modified P, N -doped carbon-based catalysts for the OER in a 1 M KOH medium. Moreover, the Fe 0.5 NiS 2 @C catalyst showed a notable Tafel slope of 90.5 mV/dec with long-dated stability even after 24 h at 10 mA/cm2. The superior OER performance of the Fe 0.5 NiS 2 @C catalysts may be due to their large surface area, sheet-like morphology with abundant active sites, fast transfer of mass and electrons, control of the electronic structure by co-treatment with heteroatoms (e.g., P and N), and the synergistic effect of bimetallic sulfides, making them favorable catalysts for the oxygen evolution reaction. Density functional theory (DFT) calculations showed that the Fe 0.5 NiS 2 @C catalyst exhibited strong H 2 O-adsorption energy. The enhanced OER activity of Fe 0.5 NiS 2 @C was attributed to its higher surface area, favorable H 2 O adsorption energy, improved electron transfer efficiency, and lower Gibbs free energy compared to those of the other proposed catalysts. [ABSTRACT FROM AUTHOR]

Developing high‐performance, high‐stability, and low‐cost nonprecious metal catalysts to enhance the performance of zinc–air batteries (ZABs) holds significant importance. A bifunctional catalyst consisting of cobalt oxide (CoO) nanocrystals on nitrogen‐doped reduced graphene oxide nanoribbons (N‐rGONR) as a novel substrate is successfully synthesized in this work. This synthesized bifunctional catalyst exhibits mesoporous structure, and remarkable synergistic effects between CoO nanocrystals and N‐rGONR, demonstrating excellent activity and durability in both oxygen reduction reactions and oxygen evolution reactions. Notably, the resulting aqueous electrolyte ZABs show a high discharge peak power density of 196 mW cm−2, a high specific capacity of 615.9 mAh g−1, and long‐time stability for 648 h. Furthermore, the assembly of 1D and 2D flexible solid‐state ZABs fabricated using this bifunctional catalyst exhibits stable electrochemical performance, even under severe deformation. These results underscore the considerable promise of implementing the CoO@N‐rGONR catalyst structure in next‐generation advanced energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

Deposition-precipitation (DP) method is commonly used to prepare the supported metal catalysts. In this study, the modification effect of the mild DP method on the photocatalytic performance of TiO2 was investigated. The TiO2 samples with DP treatment, as well as Au/TiO2 prepared under the same conditions, showed enhanced photocatalytic performance of the degradation of methylene blue (MB). · OH generated by photoexcited holes is identified as the main intermediate reactive species during the degradation reaction. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) show that TiO2(A)-17 after DP treatment has the most amount of surface OH ad − species. The presence of surface OH ad − species not only changes the surface zeta potential, favoring the attraction of cationic MB; but also depresses the electron-hole recombination, favoring photodegradation of MB by hole-produced • OH. An implication of these findings is that the modification of support properties should be taken into account while preparing supported metal catalysts using DP methods. [ABSTRACT FROM AUTHOR]

In response to the climate goal of achieving carbon neutrality by 2050, efficient electrochemical energy conversion devices are garnering increasing attention. However, the enhancement of electrochemical performance using noble metal electrocatalysts, along with cost reduction and electrode fabrication, remain significant challenges. Noble metal hybrid nanostructures, possessing multiple surface functionalities, lead to outstanding electrocatalytic performances and low‐cost potential. Strain effects can bolster the bonding strength between the noble metal layers and the substrate or core layers, while simultaneously affecting electrocatalytic performance through tuning the binding strength between catalytically active sites and reactants, including intermediates. This review encapsulates the research efforts directed towards improving the performance of noble metal electrocatalysts and provides an overview of the latest advancements in controlling the surface state of noble metals by incorporating a secondary component. We discuss systematic approaches to adjusting surface strain effects on noble metals, characterization techniques, and application case studies, while extracting key design indicators for readers to consider from a macroscopic perspective. Further, we outline the challenges encountered and current solutions when advancing noble metal catalysts from theoretical mechanisms to practical use. Finally, the perspectives on the future research of noble metal surface layer control techniques were also provided. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Axially chiral biaryls represent the most important class of atropisomers, and they widely exist in natural products and biologically active molecules. They also constitute a unique scaffold for chiral ligands and catalysts in organic synthesis. The development of synthetic methods to obtain such chiral compounds has received widespread attention, among which catalytically atroposelective ring‐opening of configurationally labile compounds represents one of the most attractive strategies. Various substrates with strained cyclic structures, such as the renowned Bringmann's lactones, can undergo asymmetric transformation into stable atropisomers. Known advancement primarily relies on metal catalyst combined with well‐designed chiral ligands, the approaches utilizing organocatalysis as a critical resolution strategy are notably scarce. In this study, we disclosed a N‐heterocyclic carbene (NHC)‐catalyzed asymmetric ring‐opening reaction of biaryl lactams via direct atroposelective nucleophilic activation. The optimized bulky carbene catalyst ensures that the reaction can proceed under mild conditions, affording the desired product with good to excellent yields and atroposelectivity. [ABSTRACT FROM AUTHOR]

A series of novel [1,2,4]triazolo[4′,3′:1,5][1,2,4]triazolo[3,4‐b][1,3,4]thiadiazines (4a‐p) were synthesized from the reaction of 4‐amino‐5‐hydrazinyl‐4H‐1,2,4‐triazole‐3‐thiol (1) with different bromoethanones (2a‐p) and substituted benzoic acids (3) via a one‐pot, three‐component reaction with good to excellent yields. The new fused tri‐cyclic system was achieved without using a catalyst and metal by cyclo‐condensation reaction through a one‐pot approach. The structures of newly synthesized molecules were confirmed by using IR, 1H‐NMR, 13C‐NMR, Mass spectral, and analytical data. Molecular docking studies were carried out for the newly synthesized compounds against human cancer receptors (2TKB) with good results. [ABSTRACT FROM AUTHOR]