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Developing conductive electrocatalysts is crucial for decreasing the ohmic loss induced by electric resistance of the catalyst layer in the large-current-density hydrogen evolution reaction (HER), which has been overlooked previously. In this study, we screen a highly conductive antiperovskite CdNNi 3 with negligible ohmic loss, as a highly active and durable HER electrocatalyst capable of unlocking ampere-scale current densities. CdNNi 3 exhibits an impressive activity (an overpotential of 235 mV) at 1 A cm -2 and maintains its performance steadily at an ampere-scale current density (at 1 A cm -2 over 400 h). Besides, the CdNNi 3 -enabled anion-exchange membrane water electrolyzer outperforms that of the benchmark Pt/C, evidenced by a reduced cell voltage of 160 mV at 1 A cm -2 , and presents a favorable stability at 1 A cm -2 . Importantly, this study experimentally discovers the dynamic surface reconstruction phenomena of antiperovskite nitrides during alkaline HER. Theoretical analysis suggests that the presence of Cd in the reconstructed surface effectively adjusts the local electronic configuration of active sites, which promotes the adsorption of OH and reduces the binding strength to H, thereby facilitating the water dissociation step and reducing the energy barrier of the potential-determining step in the HER process.

The fabrication of hybrid active sites that synergistically contain nanoclusters and single atoms (SAs) is vital for electrocatalysts to achieve excellent activity and durability. Herein, we develop a ligand-assisted pyrolysis strategy using nanoclusters (Au 4 Pd 2 (SC 2 H 4 Ph) 8 ) with alloy cores and protected ligands to build AuPd cluster sites embraced by satellite Pd SAs. In the thermal drive control process, different thermodynamic properties of the alloy atoms and the confinement effects of organic ligands allow for the mild spillover of the single-component metal Pd, resulting in the formation of AuPd alloy nanoclusters tightly encompassed by isolated Pd atoms. Experiments and theoretical calculations indicated that the satellite Pd atoms can optimize the electronic structure of the AuPd nanoclusters and Au sites in the alloy to facilitate the adsorption and dissociation of H 2 O, thus enhancing the hydrogen evolution reaction (HER) activity. The optimal AuPd NCs /Pd SAs -600 exhibits outstanding electrocatalytic activity toward HER, with overpotentials of 21 and 38 mV at 10 mA cm -2 in acidic and alkaline media, respectively. Moreover, the mass activity and turnover frequency of AuPd NCs /Pd SAs -600 are one order of magnitude higher than those of commercial Pd/C and Pt/C catalysts. This facile strategy for constructing hybrid catalytic centers using ligand-protected nanoclusters provides efficient insights for the further design of nanocluster-based electrocatalysts synergized by SAs.

Neither electrocatalytic activity nor structural stability is inconsequential in water electrolysis. Unfortunately, they have to be compromised in practice, especially in the anodic redox chemistry of lattice oxygen. Herein, the discovery of a La 1- x Ce x FeO 3 perovskite is presented which shows both good stability and high catalytic activity. Using advanced operando characterizations, it is identified that the self-healing evolution of the La 1- x Ce x FeO 3 perovskite plays a key role during water oxidation in the lattice oxygen-mediated mechanism (LOM) pathway. Unlike irreversible reconstruction, the formation of reconstructed active-phase α-FeOOH is reversed by re-crystallization of surface La 1- x Ce x FeO 3 upon return to noncatalytic conditions. The self-healing transformation of the α-FeOOH termination layer on the stable La 1- x Ce x FeO 3 core imparts remarkable long-term stability as well as excellent electrocatalytic performance. As a result, a composition La 0.9 Ce 0.1 FeO 3 @FeOOH is designed that exhibits ultralow overpotentials of 257 and 312 mV to achieve 10 and 100 mA cm -2 , respectively. The findings provide insight into self-healing behavior toward engineering perovskite oxides for efficient and stable oxygen electrocatalysis., (© 2024 Wiley‐VCH GmbH.)

Based on the experimentally reported stable and conductive two-dimensional covalent organic frameworks with copper phthalocyanine (CuPc) as building block and cyan substituted phenyl as connector (CuCOF-CN) as an electrocatalyst for CO 2 reduction reaction (RR), first principle calculations were performed on CuCOF-CN and its analog with the CN being replaced by H (CuCOF). Comparatively studied on the crystal structures, electronic properties, and CO 2 RR performance of the two catalysts found that CuCOF has reduced crystal unit size, more positive charge on Cu and CuPc segments, smaller band gap, and lower reaction barrier for CO 2 RR than CuCOF-CN. CuCOF is proposed to be good potential electrocatalyst with good environment friendliness. The substituent effect and structure-property-performance relationship would help for designing and fabricating new electrocatalysts., Competing Interests: Declarations Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

The synthetical methodology for the [Cu(dmp) 2 ] 2+/1+ (dmp = 2,9-dimethyl-1,10-phenanthroline; neocuproine) complexes has been systematically investigated by using various copper precursors, including CuCl 2 , Cu(NO 3 ) 2 , and Cu(ClO 4 ) 2 . After an anion exchange to trifluoromethanesulfonimide (TFSI), the tetra-coordinated Cu II (dmp) 2 (TFSI) 2 -Cu(ClO 4 ) 2 (7.43%) outperformed the penta-coordinated Cu II (dmp) 2 (TFSI)(NO 3 )-Cu(NO 3 ) 2 (4.30%) and Cu II (dmp) 2 (TFSI)(Cl)-CuCl 2 . Polymeric chalcogenides, including a conducting copolymeric electrode of PEDOT-PEDTT [PEDOT = poly(3,4-ethylenedioxythiophene); PEDTT = poly(3,4-ethylenedithiothiophene)] and a coordination polymeric electrode of silver bezeneselenolate ([Ag 2 (SePh) 2 ] n ; mithrene), are introduced as the electrocatalysts for [Cu(dmp) 2 ] 2+/1+ for the first time. After optimization, dye-sensitized solar cells (DSSCs) based on carbon cloth (CC)/AgSePh-30 (10.18%) showed superior electrocatalytic ability compared to the benchmark CC/Pt (7.43%) due to numerous active sites provided by electron-donating Se atoms, high film roughness, and bottom-up 2D charge transfer routes. The DSSC based on CC/PEDTT-50 (10.38%) also outperformed CC/Pt due to numerous active sites provided by electron-donating S atoms and proper energy band structure. This work sheds light on the future design and synthesis in Cu-complex mediators and functional polymeric chalcogenides for high-performance DSSCs.

MXene, a family of 2D transition metal carbides and nitrides, presents promising applications in electrocatalysis. Maximizing its large surface area is key to developing efficient non-noble-metal catalysts for the hydrogen evolution reaction (HER). In this study, oxygen-functionalized Ti 3 C 2 T x MXene (Ti 3 C 2 O x ) is synthesized and deposited gold nanoparticles (Au NPs) onto it, forming a novel composite material, Au-Ti 3 C 2 O x . By selectively removing other functional groups, mainly -O functional groups are retained on the surface, directing electron transfer from Au NPs to MXene due to electronic metal-support interaction (EMSI), thereby improving the catalytic activity of the MXene surface. Additionally, the interaction between Au NPs and -O functional groups further enhanced the overall catalytic activity, achieving an overpotential of 62 mV and a Tafel slope of 40.1 mV dec -1 at a current density of -10 mA cm -2 in 0.5 m H 2 SO 4 solution. Density functional theory calculations and scanning electrochemical microscopy with ≤150 nm resolution confirmed the enhanced catalytic efficiency due to the specific interaction between Au NPs and Ti 3 C 2 O x . This work provides a surface modification strategy to fully utilize the MXene surface and enhance the overall catalytic activity of MXene-based catalysts., (© 2024 Wiley‐VCH GmbH.)

Aluminum-sulfur batteries (ASBs) are emerging as promising energy storage systems due to their safety, low cost, and high theoretical capacity. However, it remains a challenge to overcome voltage hysteresis and short cycle life in the sulfur/Al 2 S 3 conversion reaction, which hinders the development of ASBs. Here, we studied a high-voltage ASB system based on sulfur oxidation in an AlCl 3 /urea electrolyte. Nitrogen-doped hollow nanocages (HNCs) synthesized from MOF precursors were rationally designed as sulfur/carbon composite electrodes (S@HNC), and the impact of the nitrogen species on the electrochemical performance of sulfur electrodes was systematically investigated. The S@HNC-900 achieved efficient conversion at 1.9 V, delivering a stable capacity of 197.3 mA h g -1 and a Coulombic efficiency of 93.28% after 100 cycles. Furthermore, the S@HNC-900 electrode exhibited exceptional rate capacity and 800th long-term cycling stability, retaining a capacity of 87.1 mA h g -1 at 500 mA g -1 . Ex situ XPS and XRD characterizations elucidated the redox mechanism, revealing a four-electron transfer process (S/AlSCl 7 ) at the S@HNC-900 electrode. Density functional theory calculations demonstrated that pyridinic nitrogen-enriched HNC-900 significantly enhanced the sulfur conversion reaction and facilitated the adsorption of sulfur intermediates (SCl 3 + ) on the carbon interface. This work provides critical insights into the high-voltage sulfur redox mechanism and establishes a foundation for the rational design of carbon-based electrocatalysts for the enhancement of ASB performance.

Understanding the interaction between Ru and Co components and the alloy ratio effects on the catalytic process is a technical challenge that requires a precise alloy structural design. This study proposes an effective stepwise annealing method for the construction of RuCo alloy-based electrocatalysts with varied Ru:Co ratios. Interestingly, as the concentration of Co in the first-step pyrolysis products increases, the secondary pyrolysis results in RuCo composites undergoing a transition from incomplete alloying to alloy ratios of 1:1, 1:2, and 1:8. When the alloy ratio is 1:1, more Ru n + and Co 0 transform into Ru 0 and Co 2/3+ . In 1 M KOH, RuCo-0.6/NC demonstrates outstanding catalytic performance and durability even superior to that of commercial Pt/C, delivering a lower overpotential of 16 mV at 10 mA cm -2 . DFT calculations reveal that the fast H 2 O dissociation and moderate H adsorption guarantee the superior activity of RuCo.

The hydrogen evolution reaction (HER), a crucial half-reaction in the water-splitting process, is hindered by slow kinetics, necessitating efficient electrocatalysts to lower overpotential and enhance energy conversion efficiency. Transition-metal electrode materials, renowned for their robustness and effectiveness, have risen to prominence as primary contenders in the field of energy conversion and storage research. In this investigation, we delve into the capabilities of transition metals when employed as catalysts for the HER. Furthermore, we turn our attention to carbon nanomaterials like graphene, which have exhibited tremendous potential as top-performing electrocatalysts. Nevertheless, advancements are indispensable to expand their utility and versatility. One such enhancement involves the integration of phosphorus-doped graphene. Our research focuses on the synthesis of CuS-NiTe 2 /PrGO, a nanocomposite with a crystalline structure, through a straightforward method. This nanocomposite exhibits enhanced catalytic activity for the HER, boasting a Tafel slope of 57 mV dec -1 in an acidic environment. Consequently, our findings present a straightforward and efficient approach to developing high-performance electrocatalysts for HER., Competing Interests: Declarations Competing interests The authors declare no competing interests. Ethical approval Not applicable., (© 2024. The Author(s).)

The catalytic system of biological nitrogen fixation in nature primarily relies on the "FeMo cofactor" within nitrogenase enzymes. Inspired by this natural structure, we have designed a bionic inorganic counterpart, iron-doped MoSe 2 , for the efficient electroreduction of dinitrogen to ammonia. The introduced Fe dopant significantly enhances nitrogen fixation activity of MoSe 2 . Furthermore, we constructed a heterostructure catalyst, the Fe-MoSe 2 /Mo 2 C with more versatile Mo valence states. The heterostructured electrocatalyst achieves an ammonia production rate of 3.38 μg cm -2  h -1 , and a Faradaic efficiency of 30.8 %, which is ~5 fold higher than that of pristine MoSe 2 . This study presents a novel approach for designing bionic nitrogen fixation electrocatalysts., (© 2024 Wiley-VCH GmbH.)

To address the inherent limitations of conventional carbon nanotubes (CNTs), such as their tendency to agglomerate and scarcity of catalytic sites, the development of branched carbon nanotubes (BCNTs) with a unique hierarchical structure has emerged as a promising solution. Herein, gram scale quantities of densely branched and structurally consistent Ni-Fe decorated branched CNTs (Ni-Fe@BCNT) have been prepared. This uniform and densely branched architecture ensures excellent dispersibility and superior electrical conductivity. Additionally, each branched tip is equipped with Ni-Fe particles, thereby providing numerous catalytic sites which endow them with exceptional catalytic activity for the conversion of polysulfides. The polypropylene (PP) separator modified with Ni-Fe@BCNT interlayer is fabricated as a multifunctional barrier for Li-S batteries. The experimental results demonstrate that Ni-Fe@BCNT interlayer can effectively suppress the shuttle effect of polysulfides and enhance their redox kinetics. The outstanding catalytic ability of Ni-Fe@BCNT interlayer enables batteries with high specific capacities, outstanding rate performance, and remarkable cycling stability. This approach proposed in this work paves a new path for synthesizing BCNTs and shows great potential for scaling up the production of BCNTs to address more demanding applications., (© 2024 Wiley-VCH GmbH.)

Designing high-performance anodic catalysts to drive glycerol oxidation reaction (GOR) is essential for advancing direct alcohol fuel cells. Coupling Pd with oxophilic materials is an effective strategy to enhance its intrinsic catalytic activity. In this study, we successfully synthesized Pd/Bi 2 Te 3 catalysts with tunable compositions, using Bi 2 Te 3 as a novel promoter, and applied them to the GOR for the first time. Electrocatalytic tests revealed that the activity of the Pd/Bi 2 Te 3 catalysts was closely linked to their compositions. Among these catalysts, the optimized Pd/Bi 2 Te 3 -20 % showed potential to replace the commercial Pd/C catalyst, exhibiting a peak current density 5.2 times higher than that of the benchmark Pd/C catalyst. Furthermore, improved catalytic stability and faster catalytic kinetics were observed for Pd/Bi 2 Te 3 -20 %. The synergistic effect between Pd and Bi 2 Te 3 is responsible for the high performance of the Pd/Bi 2 Te 3 -20 % catalyst., (© 2024 Wiley-VCH GmbH.)

NH 3 is a versatile solution for the storage and distribution of sustainable energy, offering high energy density and promising applications as a renewable hydrogen carrier. However, electrochemical NH 3 synthesis under ambient conditions remains challenging, such as low selectivity and efficiency, owing to the inertness of N≡N and competing reactions. In this study, a catalyst (MoC/NFC) comprising molybdenum carbide evenly dispersed on carbon doped with N and F heteroatoms was successfully synthesized using liquid-phase plasma. The MoC/NFC catalyst exhibited a maximum NH 3 yield of 115 μg h -1 mg -1 cat. with a faradaic efficiency of 1.15% at -0.7 V vs reversible hydrogen electrode in 0.1 M KOH electrolyte. Pyridinic- and pyrrolic-N atoms adjacent to the carbon pores served as active sites for N 2 adsorption and enabled N 2 triple bond cleavage. In addition, F doping contributed to N 2 activation owing to the high electronegativity of 3.98, resulting in the attraction of more electrons. These findings demonstrate a significant advancement in the development of efficient catalysts for electrochemical ammonia synthesis, potentially paving the way for scalable and sustainable NH 3 production methods that can support the growing demand for renewable energy storage solutions.

Electrocatalytic water splitting for green hydrogen production necessitates effective electrocatalysts. Currently, commercial catalysts are primarily platinum-based. Therefore, finding catalysts with comparable catalytic activity but lower cost is essential. This paper describes spinel-structured catalysts containing nickel cobaltite NiCo 2 O 4 , graphene, and additionally doped with heteroatoms. The structure and elemental composition of the obtained materials were analyzed by research methods such as TEM, SEM-EDX, XRD, XPS, and Raman spectroscopy. The electrochemical measurements showed that hybrid materials containing nickel cobaltite NiCo 2 O 4 doped with graphene are highly active catalysts in the hydrogen evolution reaction (Tafel slopes = 91 mV dec -1 , overpotential = 468 mV and onset potential = -339 mV), while in the oxygen evolution reaction (Tafel slopes = 51 mV dec -1 , overpotential = 1752 mV and onset potential = 370 mV), bare NiCo 2 O 4 without the addition of carbon has a worse activity (for HER: Tafel slopes = 120 mV dec -1 , overpotential - does not achieve and onset potential = -404 mV, for OER: Tafel slopes = 54 mV dec -1 , overpotential = 1796 mV and onset potential = 410 mV). In terms of stability, comparable results were obtained for each synthesized compound for both the HER and OER reactions., (© 2024. The Author(s).)

Electrochemical water splitting is a promising approach for hydrogen evolution reactions (HER); however, the oxygen evolution reaction (OER) remains a major bottleneck due to its high energy requirements. High-performance electrocatalysts capable of facilitating HER, OER, and overall water splitting (OWS) are highly needed to improve OER kinetics. In this work, we synthesized a trimetallic heterostructure of Ru, Ni, and Co incorporated into N-doped carbon (denoted as Ru/Ni/Co@NC) by first synthesizing Ni/Co@NC from Ni-ZIF-67 polyhedrons via high-temperature carbonization, followed by Ru doping using the galvanic replacement method. Benefiting from increased active surface sites, modulated electronic structure, and enhanced interfacial synergistic effects, Ru/Ni/Co@NC exhibited exceptional electrocatalytic performance for both HER and OER processes. The optimized Ru/Ni/Co@NC catalyst, with a minimal Ru mass ratio of ∼2.07%, demonstrated significantly low overpotential values of 34 mV for HER and 174 mV for OER at a current density of 10 mA/cm 2 with corresponding Tafel slope values of 33.42 and 34.39 mV/dec, respectively. Further, the optimized catalyst was loaded onto carbon paper and used as anode and cathode materials for alkaline water splitting. Interestingly, a low cell voltage of just 1.44 V was obtained. The enhanced electrolytic performance was further elaborated by density functional theory (DFT) calculations, which confirmed that Ru doping in Ni/Co introduced additional active sites for H*, enhancing adsorption/desorption abilities for HER (Δ G H* = -0.30 eV), lowering water dissociation barrier (Δ G b = 0.49 eV) and reducing the energy barrier for the rate-determining step of OER (O* → OOH*) to 1.62 eV in an alkaline environment. These findings reflect the significant potential of ZIF-67-based catalysts in energy conversion and storage applications.

The sluggish reaction kinetics of the anodic oxygen evolution reaction (OER) and the inadequate catalytic performance of non-noble metal-based electrocatalysts represent substantial barriers to the development of anion exchange membrane water electrolyzer (AEMWE). This study performed the synthesis of a three-dimensional (3D) nanoflower-like electrocatalyst (CFMO) via a simple one-step method. The substitution of Co with Fe in the structure induces a localized oxide path mechanism (LOPM), facilitating direct O-O radical coupling for enhanced O 2 evolution. The optimized CFMO-2 electrocatalyst demonstrates superior OER performance, achieving an overpotential of 217 mV at 10 mA cm -2 , alongside exceptional long-term stability with minimal degradation after 1000 h of operation in 1.0 M KOH. These properties surpass most of conventional noble metal-based electrocatalysts. Furthermore, the assembled AEMWE system, utilizing CFMO-2, operates with a cell voltage of 1.65 V to deliver 1.0 A cm -2 . In situ characterizations reveal that, in addition to the traditional adsorbate evolution mechanism (AEM) at isolated Co sites, a new LOPM occurred around the Fe and Co bimetallic sites. First-principles calculations confirm the LOPM greatly reduced the energy barriers. This work highlights the potential of LOPM for improving the design of non-noble metal-based electrocatalysts and the development of AEMWE., (© 2024 Wiley-VCH GmbH.)

The development of efficient, high-performance catalysts for hydrogen evolution reaction (HER) remains a significant challenge, especially in seawater media. Here, RuIr alloy catalysts are prepared by the polyol reduction method. Compared with single-metal catalysts, the RuIr alloy catalysts exhibited higher activity and stability in seawater electrolysis due to their greater number of reactive sites and solubility resistance. The RuIr alloy has an overpotential of 75 mV@10 mA cm -2 , which is similar to that of Pt/C (73 mV), and can operate stably for 100 hours in alkaline seawater. Density functional theory (DFT) calculations indicate that hydrogen atoms adsorbed at the top sites of Ru and Ir atoms are more favorable for HER and are most likely to be the reactive sites. This work provides a reference for developing highly efficient and stable catalysts for seawater electrolysis., (© 2024 Wiley‐VCH GmbH.)

Lithium-oxygen (Li-O 2 ) battery with large theoretical energy density (≈3500 Wh kg -1 ) is one of the most promising energy storage and conversion systems. However, the slow kinetics of oxygen electrode reactions inhibit the practical application of Li-O 2 battery. Thus, designing efficient electrocatalysts is crucial to improve battery performance. Here, Ti 3 C 2 MXene/Mo 4/3 B 2-x MBene superlattice is fabricated its electrocatalytic activity toward oxygen redox reactions in Li-O 2 battery is studied. It is found that the built-in electric field formed by a large work function difference between Ti 3 C 2 and Mo 4/3 B 2-x will power the charge transfer at the interface from titanium (Ti) site in Ti 3 C 2 to molybdenum (Mo) site in Mo 4/3 B 2-x . This charge transfer increases the electron density in 4d orbital of Mo site and decreases the d-band center of Mo site, thus optimizing the adsorption of intermediate product LiO 2 at Mo site and accelerating the kinetics of oxygen electrode reactions. Meanwhile, the formed film-like discharge products (Li 2 O 2 ) improve the contact with electrode and facilitate the decomposition of Li 2 O 2 . Based on the above advantages, the Ti 3 C 2 MXene/Mo 4/3 B 2-x MBene superlattice-based Li-O 2 battery exhibits large discharge specific capacity (17 167 mAh g -1 ), low overpotential (1.16 V), and superior cycling performance (475 cycles)., (© 2024 Wiley‐VCH GmbH.)

N-regulated three-dimensional (3D) turf-like carbon material loaded with FeCoNi nanoalloys (F-CNS-CNT), composed of carbon nanotubes (CNT) grown in situ on carbon nanosheets(CNS), was synthesized using a low-temperature solution combustion method and organic compounds rich in pyridinic-N. This distinct structure significantly expands the effective electrochemical surface area, revealing an abundance of active sites and enhancing the mass transfer capability for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Both experimental observations and theoretical calculations corroborate that the synergy between the FeCoNi nanoalloy and the highly pyridinic N-doped carbon substrate optimizes the adsorption and desorption-free energy of oxygen intermediates, resulting in a remarkable improvement of intrinsic ORR/OER activity. Therefore, the derived F-CNS-CNT electrocatalyst can present a favorable half-wave potential of 0.85 V (ORR) and a lower overpotential of 260 mV (corresponding to a current density of 10 mA cm -2 , OER) in alkaline media. Moreover, when employed in the air cathode of a flowable zinc-air battery, the electrocatalyst exhibits exceptional discharge and charge performance, including a high power density of 144.6 mW cm -2 , a high specific capacity of 801 mAh g -1 , and an impressive cycling stability of 600 cycles at a current density of 10 mA cm -2 . Notably, these results markedly surpass those of the commercial catalyst Pt/C + IrO 2 ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Metal phosphide, as a highly conductive, chemically stable catalyst material, modulating its hydrogen adsorption is crucial to enhance hydrogen evolution reaction (HER) activity. In this study, we propose a double loading strategy to build Ag and AgP 2 heterogeneous structures on Ni 2 P nanosheets (Ag-AgP 2 /Ni 2 P). This is the first application of AgP 2 materials in HER. This innovative synthesis was achieved by liquid-phase adsorption of precursors and heat-treatment phosphorization, surface adsorbed AgNO 3 is converted to Ag-AgP 2 double loading at the same time as Ni 2 P formation. Density functional theory (DFT) calculations reveal that the double loading structure optimizes charge distribution and d-band center. Its hydrogen adsorption free energy is closer to electroneutrality than that of single loading and simple heterostructures. Benefiting from the special structure, Ag-AgP 2 /Ni 2 P exhibits excellent HER performance in alkaline media, requiring only 78 mV overpotential to reach 10 mA cm -2 and stability up to 200 h. This dual loading strategy broadens the perspective of heterogeneous electrocatalyst development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

A novel oxygen evolution reaction (OER) electrocatalyst was prepared by a synthesis strategy consisting of the solvothermal growth of Ni 3 S 2 nanostructures on Ni foam, followed by hydrothermal incorporation of Fe species (Fe-Ni 3 S 2 /Ni foam). This electrocatalyst displayed a low OER overpotential of 230 mV at 100 mA·cm -2 , a low Tafel slope of 43 mV·dec -1 , and constant performance at an industrially relevant current density (500 mA·cm -2 ) over 100 h in a 1.0 M KOH electrolyte, despite a minor loss of Fe in the process. Based on a detailed characterization by (in situ) Raman spectroscopy, (quasi-in situ) XPS, SEM, TEM, XRD, ICP-AES, EIS, and C dl analysis, the high OER activity and stability of Fe-Ni 3 S 2 /Ni foam were attributed to the nanostructuring of the surface in the form of stable nanosheets and to the combination of Ni 3 S 2 granting suitable electrical conductivity with newly formed NiFe-based (oxy)hydroxides at the surface of the material providing the active sites for OER.

Direct seawater electrolysis is emerging as a promising renewable energy technology for large-scale hydrogen generation. The development of Os-Ni 4 Mo/MoO 2 micropillar arrays with strong metal-support interaction (MSI) as a bifunctional electrocatalyst for seawater electrolysis is reported. The micropillar structure enhances electron and mass transfer, extending catalytic reaction steps and improving seawater electrolysis efficiency. Theoretical and experimental studies demonstrate that the strong MSI between Os and Ni 4 Mo/MoO 2 optimizes the surface electronic structure of the catalyst, reducing the reaction barrier and thereby improving catalytic activity. Importantly, for the first time, a dual Cl - repelling layer is constructed by electrostatic force to safeguard active sites against Cl - attack during seawater oxidation. This includes a strong Os─Cl adsorption and an in situ-formed MoO 4 2- layer. As a result, the Os-Ni 4 Mo/MoO 2 catalyst exhibits an ultralow overpotential of 113 and 336 mV to reach 500 mA cm -2 for HER and OER in natural seawater from the South China Sea (without purification, with 1 m KOH added). Notably, it demonstrates superior stability, degrading only 0.37 µV h -1 after 2500 h of seawater oxidation, significantly surpassing the technical target of 1.0 µV h -1 set by the United States Department of Energy., (© 2024 Wiley‐VCH GmbH.)

Urea, one of the most widely used nitrogen-containing fertilizers globally, is essential for sustainable agriculture. Improving its production is crucial for meeting the increasing demand for fertilizers. Electrocatalytic co-reduction of CO₂ and nitrogenous compounds (NO₂ - /NO₃ - ) has emerged as a promising strategy for green and energy-efficient urea synthesis. However, challenges such as slow reaction kinetics and complex multi-step electron transfers have hindered the development of efficient urea synthesis methods. This review explores recent advances in the electrocatalytic C-N coupling process, focusing on bimetallic catalysts, metal oxide/hydroxide catalysts, and carbon-based catalysts. The review also discusses the future prospects of designing effective catalysts for electrocatalytic C-N coupling to improve urea synthesis., (© 2024 Wiley-VCH GmbH.)

Hydrogen peroxide (H 2 O 2 ) is a versatile and zero-emission material that is widely used in the industrial, domestic, and healthcare sectors. It is clear that it plays a critical role in advancing environmental sustainability, acting as a green energy source, and protecting human health. Conventional production techniques focused on anthraquinone oxidation, however, electrocatalytic synthesis has arisen as a means of utilizing renewable energy sources in conjunction with available resources like oxygen and water. These strides represent a substantial change toward more environmentally and energy-friendly H 2 O 2 manufacturing techniques that are in line with current environmental and energy goals. This work reviews recent advances in two-electron water oxidation reaction (2e-WOR) electrocatalysts, including design principles and reaction mechanisms, examines catalyst design alternatives and experimental characterization techniques, proposes standardized assessment criteria, investigates the impact of the interfacial milieu on the reaction, and discusses the value of in situ characterization and molecular dynamics simulations as a supplement to traditional experimental techniques and theoretical simulations, as shown in Figure 1. The review also emphasizes the importance of device design, interface, and surface engineering in improving the production of H 2 O 2 . Through adjustments to the chemical microenvironment, catalysts can demonstrate improved performance, opening the door for commercial applications that are scalable through tandem cell development., (© 2024 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

The H 2 O 2 generation via the green electrochemical process is of high interest. For the H 2 O 2 electrochemical generation, the oxygen reduction reaction (ORR) is important. Unfortunately, the ORR is kinetically sluggish and catalysts are needed. However, noble metal ORR catalysts are pricy and scarcely applicable in applications. Therefore, non-precious metal catalysts are desired. Heteroatom-doped carbons show promise as metal-free ORR catalysts. The ORR catalytic activity will be enhanced by the carbon's sp 2 and/or sp 3 engineering. For N, S co-Cdoped and sp 2 /sp 3 modulated carbon, a polymerizable ionic liquid of hydrolyzed vinyl imidazolium was studied. The carbon is studied as a metal-free catalyst for the ORR via the 2e - process. It is possible to get an onset potential of 0.88 V vs. RHE with approximately 50 % selectivity for the H 2 O 2 . The current study offers a simple technique for synthesizing heteroatom-doped sp 2 /sp 3 designed carbon as catalysts for the electroreduction of O 2 to produce H 2 O 2 , and a new way of tunning the sp 3 /sp 2 carbon catalytic activity by modulating the ionic liquid., (© 2024 Wiley-VCH GmbH.)

Direct formic acid fuel cells (DFAFCs) stand out for portable electronic devices owing to their ease of handling, abundant fuel availability, and high theoretical open circuit potential. However, the practical application of DFAFCs is hindered by the unsatisfactory performance of electrocatalysts for the sluggish anodic formic acid oxidation reaction (FAOR). Palladium (Pd) based nanomaterials have shown promise for FAOR due to their highly selective reaction mechanism, but maintaining high electrocatalytic durability remains challenging. In this study, a novel Pd-based electrocatalyst (UiO-Pd-E) is reported with exceptional durability and activity for FAOR, which can be attributed to the Pd nanoparticles encapsulated within a carbon framework where concurrent chemical alloying of Pd and Zr occurs. Further, the UiO-Pd-E demonstrates noteworthy multifunctionality in various electrochemical reactions including electrocatalytic ethanol oxidation reaction (EOR) and oxygen reduction reaction (ORR) in addition to the FAOR, highlighting its practical potentials., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

The rational design of polysulfide electrocatalysts is of vital importance to achieve longevous Li─S batteries. Notwithstanding fruitful advances made in elevating electrocatalytic activity, efforts to regulate precatalyst phase evolution and protect active sites are still lacking. Herein, an in situ graphene-encapsulated bimetallic model catalyst (CoNi@G) is developed for striking a balance between electrocatalytic activity and stability for sulfur electrochemistry. The layer numbers of directly grown graphene can be dictated by tuning the synthetic duration. Exhaustive experimental and theoretical analysis comprehensively reveals that the tailored graphene chainmail boosts catalytic durability while guaranteeing moderate phase evolution, accordingly attaining a decorated surface sulfidation with advanced catalytic essence. Benefiting from the sustainable polysulfide electrocatalysis, CoNi@G enabled sulfur electrodes to harvest a capacity output of 1276.2 mAh g -1 at 0.2 C and a negligible capacity decay of 0.055% per cycle after 1000 cycles at 1.0 C. Such a maneuver can be readily extended to other metallic catalysts including NiFe, CoFe, or Co. The work elucidates the precatalyst phase evolution mechanism through a controllable graphene-armored strategy, offering meaningful guidance to realize durable electrocatalysts in Li─S batteries., (© 2024 Wiley‐VCH GmbH.)

High-entropy perovskite oxides, in which the B-type metal site of perovskite oxides (ABO 3 ) is occupied by over five kinds of transition metal ions, show promising applications in energy storage and conversion fields. Herein, high-entropy perovskite oxides (LaSr(5TM)O 3 ) composed of Cr, Mn, Fe, Co, and Ni at the B-type metal site are prepared as oxygen electrocatalysts for Li-O 2 batteries. The presence of compressive strain in LaSr(5TM)O 3 effectively regulates the 3d orbit occupancy of the active Co site (Co 2+ → Co 3+ ) and lifts the energy level of the Co d-band center, thus leading to enhanced adsorption toward the LiO 2 intermediate on Co sites. Furthermore, the high electron-drawing capability of Cr sites ensures sufficient electron exchange and further strengthens the adsorption of LiO 2 . As expected, the Li-O 2 battery with a LaSr(5TM)O 3 electrode delivers a low overpotential (0.79 V) and superior cyclability (226 cycles). This study provides a meaningful strain strategy to improve the electrocatalytic activity of multicomponent oxides via fabricating high-entropy materials.

Tin (Sn)-based materials are expected to realize efficient CO 2 electroreduction into formate. Herein, we constructed a heterojunction by depositing Cu on Cu-doped SnS 2 nanosheets. During the electrochemical reaction, this heterojunction evolves to a highly active phase of Cu 2 O@Cu 6 Sn 5 while maintaining its two-dimensional morphology. Specifically, a partial current density of 35 mA cm -2 with an impressive faradaic efficiency of 93 % for formate production was achieved over the evolved heterojunction. In situ and ex situ experiments elucidated the formation mechanism of the Cu₂O@Cu₆Sn₅ heterojunction. Cu₆Sn₅ nanosheets were formed via a stepwise desulfurization process, while Cu₂O was generated through its reaction with hydroxyl radicals. This evolved heterojunction with a high electrochemically active surface area synergistically stabilized the *OCHO intermediate, thereby significantly enhancing the selectivity and activity. Our findings provide insight into the structural evolution process and guide the development of selective electrocatalysts for CO 2 reduction., (© 2024 Wiley-VCH GmbH.)

Electrocatalytic nitrate reduction reaction (NO 3 - RR) is an important route for sustainable NH 3 RR electrocatalysts, however, there is plenty of room to improve in their performance, calling for new design principles. Herein, a MOF-on-MOF heterostructured electrocatalyst with interfacial dual active sites and build-in electric field is fabricated for efficient NO 3 - RR electrocatalysts, however, there is plenty of room to improve in their performance, calling for new design principles. Herein, a MOF-on-MOF heterostructured electrocatalyst with interfacial dual active sites and build-in electric field is fabricated for efficient NO 3 - RR to NH 3 production. By growing Co-HHTP (HHTP=2,3,6,7,10,11-hexahydroxytriphenylene) nanorods on Ni-BDC (BDC=1,4-benzenedicarboxylate) nanosheets, experimental and theoretical investigations demonstrate the formation of Ni-O-Co bonds at the interface of MOF-on-MOF heterostructure, leading to dual active sites tailed for NO 3 - RR. The Ni sites facilitate the adsorption and activation of NO 3 - , while the Co sites boost the H 2 O decomposition to supply active hydrogen (H ads ) for N-containing intermediates hydrogenation on adjacent Ni sites, cooperatively reducing the energy barriers of NO 3 - RR process. Together with the accelerated electron transfer enabled by built-in electric field, remarkable NO 3 - RR performance is achieved with an NH 3 yield rate of 11.46 mg h -1  cm -2 and a Faradaic efficiency of 98.4 %, outperforming most reported MOF-based electrocatalysts. This work provides new insights into the design of high-performance NO 3 - RR electrocatalysts., (© 2024 Wiley-VCH GmbH.)

A dynamic-regulated Pd-Fe-N electrocatalyst was effectively constructed with electron-donating and back-donating effects, which serves as an efficient engineering strategy to optimize the electrocatalytic activity. The designed PdFe 3 /FeN features a comprehensive electrocatalytic performance toward the nitrogen reduction reaction (NRR, yield rate of 29.94 μg h -1 mg cat -1 and FE of 38.43% at -0.2 V vs RHE) and oxygen evolution reaction (OER, 308 mV at 100 mA cm -2 ). Combining in situ ATR-FTIR, XAS, and DFT results, the role of the interstitial-N-dopant-induced electron sponge effect has been significantly elucidated in strengthening the electrocatalytic NRR process. Specifically, the introduction of a N dopant, an electron acceptor, initiates the generation of robust Lewis-acidic Fe sites, facilitating free N 2 capture and bonding. Simultaneously, after NH 3 deportation through weakening the Lewis acidity of Fe centers. Besides, the electron-deficient Fe sites contribute to the reconstruction of FeOOH, the real active species during the OER, which accelerates the four-electron reaction kinetics. This research offers a perspective on electrocatalyst design, potentially facilitating the evolution of advanced material engineering for efficient electrocatalytic synthesis and energy storage.3 deportation through weakening the Lewis acidity of Fe centers. Besides, the electron-deficient Fe sites contribute to the reconstruction of FeOOH, the real active species during the OER, which accelerates the four-electron reaction kinetics. This research offers a perspective on electrocatalyst design, potentially facilitating the evolution of advanced material engineering for efficient electrocatalytic synthesis and energy storage.

As the anode reaction of proton exchange membrane water electrolysis (PEMWE), the acidic oxygen evolution reaction (OER) is one of the main obstacles to the practical application of PEMWE due to its sluggish four-electron transfer process. The development of high-performance acidic OER electrocatalysts has become the key to improving the reaction kinetics. To date, although various excellent acidic OER electrocatalysts have been widely researched, Ir-based nanomaterials are still state-of-the-art electrocatalysts. Hence, a comprehensive and in-depth understanding of the reaction mechanism of Ir-based electrocatalysts is crucial for the precise optimization of catalytic performance. In this review, the origin and nature of the conventional adsorbate evolution mechanism (AEM) and the derived volcanic relationship on Ir-based electrocatalysts for acidic OER processes are summarized and some optimization strategies for Ir-based electrocatalysts based on the AEM are introduced. To further investigate the development strategy of high-performance Ir-based electrocatalysts, several unconventional OER mechanisms including dual-site mechanism and lattice oxygen mediated mechanism, and their applications are introduced in detail. Thereafter, the active species on Ir-based electrocatalysts at acidic OER are summarized and classified into surface Ir species and O species. Finally, the future development direction and prospect of Ir-based electrocatalysts for acidic OER are put forward., (© 2024 Wiley‐VCH GmbH.)

Doping transition metal oxide spinels with metal ions represents a significant strategy for optimizing the electronic structure of electrocatalysts. Herein, a bimetallic Fe and Ru doping strategy to fine-tune the crystal structure of CoV 2 O 4 spinel for highly enhanced oxygen evolution reaction (OER) is presented performance. The incorporation of Fe and Ru is observed at octahedral sites within the CoV 2 O 4 structure, effectively modulating the electronic configuration of Co. Density functional theory calculations have confirmed that Fe acts as a novel reactive site, replacing V. Additionally, the synergistic effect of Fe, Co, and Ru effectively optimizes the Gibbs free energy of the intermediate species, reduces the reaction energy barrier, and accelerates the kinetics toward OER. As expected, the best-performing CoVFe 0.5 Ru 0.5 O 4 displays a low overpotential of 240 mV (@10 mA cm -2 ) and a remarkably low Tafel slope of 38.9 mV dec -1 , surpassing that of commercial RuO 2 . Moreover, it demonstrates outstanding long-term durability lasting for 72 h. This study provides valuable insights for the design of highly active polymetallic spinel electrocatalysts for energy conversion applications., (© 2024 Wiley‐VCH GmbH.)

Constructing I single-atom (I SA ) doped CoP electrocatalyst for HER is extremely challenging and has not been reported to date. Herein, an I SA doping-phosphatization strategy is proposed to prepare a novel I single-atom doped P-rich CoP n nanocluster@CoP electrocatalyst (I SA -CoP n /CoP) with enhanced HER performance first. I SA -CoP n /CoP shows a low overpotential of only 44 and 81 mV in 0.5 m H 2 SO 4 solution, to drive a current density of 10 and 100 mA cm -2 . I SA and P-rich CoP n nanocluster show unique synergies, which can optimize the H adsorption energy and accelerate the kinetics of HER in the CoP system. The intermediate I─H bond vibration peak is directly observed through in situ Raman testing, demonstrating that I SA doping helps accelerate the HER process. Additionally, the ΔG H of I SA -CoP n /CoP is only 0.05 eV by density functional theory (DFT) calculation, which is conducive to H 2 evolution., (© 2024 Wiley‐VCH GmbH.)

Over the last decade, carbon-based metal-free electrocatalysts (C-MFECs) have become important in electrocatalysis. This field is started thanks to the initial discovery that nitrogen atom doped carbon can function as a metal-free electrode in alkaline fuel cells. A wide variety of metal-free carbon nanomaterials, including 0D carbon dots, 1D carbon nanotubes, 2D graphene, and 3D porous carbons, has demonstrated high electrocatalytic performance across a variety of applications. These include clean energy generation and storage, green chemistry, and environmental remediation. The wide applicability of C-MFECs is facilitated by effective synthetic approaches, e.g., heteroatom doping, and physical/chemical modification. These methods enable the creation of catalysts with electrocatalytic properties useful for sustainable energy transformation and storage (e.g., fuel cells, Zn-air batteries, Li-O 2 batteries, dye-sensitized solar cells), green chemical production (e.g., H 2 O 2 , NH 3 , and urea), and environmental remediation (e.g., wastewater treatment, and CO 2 conversion). Furthermore, significant advances in the theoretical study of C-MFECs via advanced computational modeling and machine learning techniques have been achieved, revealing the charge transfer mechanism for rational design and development of highly efficient catalysts. This review offers a timely overview of recent progress in the development of C-MFECs, addressing material syntheses, theoretical advances, potential applications, challenges and future directions., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Water electrolysis is considered the cleanest method for hydrogen production. However, the widespread popularization of water splitting is limited by the high cost and scarce resources of efficient platinum group metals. Hence, it is imperative to develop an economical and high-performance electrocatalyst to improve the efficiency of hydrogen evolution reaction (HER). In this study, a hierarchical porous sandwich structure is fabricated through dealloying FeCoNiCuAl 2 Mn high-entropy alloy (HEA). This free-standing electrocatalyst shows outstanding HER performance with a very small overpotential of 9.7 mV at 10 mA cm -2 and a low Tafel slope of 56.9 mV dec -1 in 1 M KOH solution, outperforming commercial Pt/C. Furthermore, this electrocatalytic system recorded excellent reaction stability over 100 h with a constant current density of 100 mA cm -2 . The enhanced electrochemical activity in high-entropy alloys results from the cocktail effect, which is detected by density functional theory (DFT) calculation. Additionally, micron- and nano-sized pores formed during etching boost mass transfer, ensuring sustained electrocatalyst performance even at high current densities. This work provides a new insight for development in the commercial electrocatalysts for water splitting., (© 2024 Wiley‐VCH GmbH.)

In this study, the copper-nickel (Cu-Ni) bimetallic electrocatalysts for electrochemical CO 2 reduction reaction(CO 2 RR) are fabricated by taking the finely designed poly(ionic liquids) (PIL) containing abundant Salen and imidazolium chelating sites as the surficial layer, wherein Cu-Ni, PIL-Cu and PIL-Ni interaction can be readily regulated by different synthetic scheme. As a proof of concept, Cu@Salen-PIL@Ni(NO 3 ) 2 and Cu@Salen-PIL(Ni) hybrids differ significantly in the types and distribution of Ni species and Cu species at the surface, thereby delivering distinct Cu-Ni cooperation fashion for the CO 2 RR. Remarkably, Cu@Salen-PIL@Ni(NO 3 ) 2 provides a C2+ faradaic efficiency (FE C2+ ) of 80.9% with partial current density (j C 2+ ) of 262.9 mA cm -2 at -0.80 V (versus reversible hydrogen electrode, RHE) in 1 m KOH in a flow cell, while Cu@Salen-PIL(Ni) delivers the optimal FE C2+ of 63.8% at j C2+ of 146.7 mA cm -2 at -0.78 V. Mechanistic studies indicates that the presence of Cu-Ni interfaces in Cu@Salen-PIL@Ni(NO 3 ) 2 accounts for the preserve of high-valence Cu(I) species under CO 2 RR conditions. It results in a high activity of both CO 2 -to-CO conversion and C-C coupling while inhibition of the competitive HER., (© 2024 Wiley‐VCH GmbH.)

Phase engineering is promising to increase the intrinsic activity of the catalyst toward hydrogen evolution reaction (HER). However, the polymorphism interface is unstable due to the presence of metastable phases. Herein, phase engineering and dispersion stabilization are applied simultaneously to boost the HER activity of cobalt without sacrificing the stability. A fast and facile approach (plasma cathodic electro deposition) is developed to prepare cobalt film with a hetero-phase structure. The polymorphs of cobalt are realized through reduced stacking fault energy due to the doping of Mo, and the high temperature treatment resulted from the plasma discharge. Meanwhile, homogeneously dispersed oxide/carbide nanoparticles are produced from the reaction of plasma-induced oxygen/carbon atoms with electro-deposited metal. The existence of rich polymorphism interface and oxide/carbide help to facilitate H 2 production by the tuning of electronic structure and the increase of active sites. Furthermore, oxide/carbide dispersoid effectively prevents the phase transition through a pinning effect on the grain boundary. As-prepared Co-hybrid/CoO_MoC exhibits both high HER activity and robust stability (44 mV at 10 mA cm -2 , Tafel slope of 53.2 mV dec -1 , no degradation after 100 h test). The work reported here provides an alternate approach to the design of advanced HER catalysts for real application., (© 2024 Wiley‐VCH GmbH.)

Efficient production of green hydrogen energy is crucial in addressing the energy crisis and environmental concerns. The oxygen evolution reaction (OER) poses a challenge in conventional overall water electrolysis due to its slow thermodynamically process. Urea oxidation reaction (UOR) offers an alternative anodic oxidation method that is highly efficient and cost-effective, with favorable thermodynamics and sustainability. Recently, there has been limited research on bifunctional catalysts that exhibit excellent activity for both OER and UOR reactions. In this study, we developed a selenium and iron co-doped nickel sulfide (SeFe-Ni 3 S 2 ) catalyst that demonstrated excellent Tafel slopes of 53.9 mV dec -1 and 16.4 mV dec -1 for OER and UOR, respectively. Density Functional Theory (DFT) calculations revealed that the introduction of metal (iron) and nonmetallic elements (selenium) was found to coordinate the d-band center, resulting in improved adsorption/desorption energies of the catalysts and reduced the overpotentials and limiting potentials for OER and UOR, respectively. This activity enhancement can be attributed to the altered electronic coordination structure after the introduction of selenium (Se) and iron (Fe), leading to an increase in the intrinsic activity of the catalyst. This work offers a new strategy for bifunctional catalysts for OER and UOR, presenting new possibilities for the future development of hydrogen production and novel energy conversion technologies. It contributes towards the urgent search for technologies that efficiently produce green hydrogen energy, providing potential solutions to mitigate the energy crisis and protect the environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The optimization of metal-support interactions is used to fabricate noble metal-based nanoclusters with high activity for hydrogen evolution reaction (HER) in acid media. Specifically, the oxygen-defective Mn 3 O 4 nanosheets supported Pt nanoclusters of ≈1.71 nm in diameter (Pt/V·-Mn 3 O 4 NSs) are synthesized through the controlled solvothermal reaction. The Pt/V·-Mn 3 O 4 NSs show a superior activity and excellent stability for the HER in the acidic media. They only require an overpotential of 19 mV to drive -10 mA cm -2 and show negligible activity loss at -10 and -250 mA cm -2 for >200 and >60 h, respectively. Their Pt mass activity is 12.4 times higher than that of the Pt/C and even higher than those of many single-atom based Pt catalysts. DFT calculations show that their high HER activity arises mainly from the strong metal-support interaction between Pt and Mn 3 O 4 . It can facilitate the charge transfer from Mn 3 O 4 to Pt, optimizing the H adsorption on the catalyst surface and promoting the evolution of H 2 through the Volmer-Tafel mechanism. The oxygen vacancies in the V·-Mn 3 O 4 NSs are found to be inconducive to the high activity of the Pt/V·-Mn 3 O 4 NSs, highlighting the great importance to reduce the vacancy levels in V·-Mn 3 O 4 NSs., (© 2024 Wiley‐VCH GmbH.)

The electrosynthesis of multi-carbon chemicals from excess carbon dioxide (CO 2 ) is an area of great interest for research and commercial applications. However, improving both the yield of CO 2 -to-ethanol conversion and the stability of the catalyst at the same time is proving to be a challenging issue. Here it is proposed to stabilize active Cu(I) and In dual sites with sulfur defects through an electro-driven intercalation strategy, which leads to the delocalization of electron density that enhances orbital hybridizations between the Cu-C and In-H bonds. Hence, the energy barrier for the rate-limiting *CHO formation step is reduced toward the key *OCHCHO* formation during ethanol production, which is also facilitated by the combined Cu site enabling C-C coupling and In site with a higher oxygen affinity based on both thermodynamic and kinetic calculations. Accordingly, such dual-site catalyst achieves a high partial current density toward ethanol of 409 ± 15 mA cm⁻ 2 for over 120 h. Furthermore, a scaled-up flow cell is assembled with an industrial-relevant current of 5.7 A for over 36 h, in which the carbon loss is less than 2.5% and single-pass carbon efficiency is ≈19%., (© 2024 Wiley‐VCH GmbH.)

The catalytic activity of platinum for CO oxidation depends on the interaction of electron donation and back-donation at the platinum center. Here we demonstrate that the platinum bromine nanoparticles with electron-rich properties on bromine bonded with sp-C in graphdiyne (PtBr NPs/Br-GDY), which is formed by bromine ligand and constitutes an electrocatalyst with a high CO-resistant for methanol oxidation reaction (MOR). The catalyst showed peak mass activity for MOR as high as 10.4 A mg Pt -1 , which is 20.8 times higher than the 20 % Pt/C. The catalyst also showed robust long-term stability with slight current density decay after 100 hours at 35 mA cm -2 . Structural characterization, experimental, and theoretical studies show that the electron donation from bromine makes the surface of platinum catalysts highly electron-rich, and can strengthen the adsorption of CO as well as enhance π back-donation of Pt to weaken the C-O bond to facilitate CO electrooxidation and enhance catalytic performance during MOR. The results highlight the importance of electron-rich structure among active sites in Pt-halogen catalysts and provide detailed insights into the new mechanism of CO electrooxidation to overcome CO poisoning at the Pt center on an orbital level., (© 2024 Wiley-VCH GmbH.)

The rational design of pH-universal electrocatalyst with high-efficiency, low-cost and large current output suitable for industrial hydrogen evolution reaction (HER) is crucial for hydrogen production via water splitting. Herein, phase engineering of ruthenium (Ru) electrocatalyst comprised of metastable unconventional face-centered cubic (fcc) and conventional hexagonal close-packed (hcp) crystalline phase supported on nitrogen-doped carbon matrix (fcc/hcp-Ru/NC) is successfully synthesized through a facile pyrolysis approach. Fascinatingly, the fcc/hcp-Ru/NC displayed excellent electrocatalytic HER performance under a universal pH range. To deliver a current density of 10 mA cm -2 , the fcc/hcp-Ru/NC required overpotentials of 16.8, 23.8 and 22.3 mV in 1 M KOH, 0.5 M H 2 SO 4 and 1 M phosphate buffered solution (PBS), respectively. Even to drive an industrial-level current density of 500 and 1000 mA cm -2 , the corresponding overpotentials are 189.8 and 284 mV in alkaline, 202 and 287 mV in acidic media, respectively. Experimental and theoretical calculation result unveiled that the charge migration from fcc-Ru to hcp-Ru induced by work function discrepancy within fcc/hcp-Ru/NC regulate the d-band center of Ru sites, which facilitated the water adsorption and dissociation, thus boosting the electrocatalytic HER performance. The present work paves the way for construction of novel and efficient electrocatalysts for energy conversion and storage., (© 2024 Wiley‐VCH GmbH.)

Urea electrolysis can address pressing environmental concerns caused by urea-containing wastewater while realizing energy-saving hydrogen production. Highly efficient and affordable electrocatalysts are indispensable for realizing the great potential of this emerging technology. Among the numerous candidates, α-Ni(OH) 2 has the merits of good electrocatalytic activity, adjustable heteroelement doping, and low cost; consequently, it has received tremendous attention in the electrolytic fields. Herein, a Y 3+ -doping strategy is developed to effectively enhance the catalytic performance of nickel hydroxide in the urea oxidation reaction (UOR). Our results show that Y 3+ incorporation successfully modulates the electronic structure of α-Ni(OH) 2 by inducing Ni 3+ formation in the crystal lattice to initiate direct UOR, facilitates the Ni 3+ /Ni 2+ redox transition with higher current responses to promote indirect UOR, and maintains the structural stability of YNi-10 (Ni 2+ /Y 3+ molar ratio = 1:0.1) during long-term UOR operation. Owing to these features, the obtained YNi-10 sample exhibits a higher current density (127 vs 79 mA cm -2 at 1.5 V), a lower Tafel slope (48 vs 75 mV dec -1 ), a larger potential difference between the UOR and oxygen evolution reaction (OER, 0.26 vs 0.22 V at 80 mA cm -2 ), a higher reaction rate constant (1.1 × 10 5 vs 3.1 × 10 3 cm 3 mol -1 s -1 ), and a reduced activation energy of UOR (2.9 vs 14.8 kJ mol -1 ) compared with the Y-free counterpart (YNi-0). This study presents a promising strategy to simultaneously boost direct and indirect UORs, providing new insights for further developing high-performance electrocatalysts.

Although MoS 2 quantum dots with abundant edge sites have been regarded as promising eletrode materials for the hydrogen evolution reaction (HER), their electrocatalytic capacity still requires improvements in actual applications. Herein. we demonstrate a controllable and robust bottom-up approach to build 3D crosslinked graphene-Ti 3 C 2 T x MXene frameworks decorated with MoS 2 quantum dots (MQD/RGO-MX) via a convenient co-assembly process. The novel structural design gives the MQD/RGO-MX nanoarchitectures a series of superior textural attributes, including 3D interconnected networks, continuous meso- and macropores, well-dispersed quantum dots, ameliorative electronic configuration, and excellent electrical conductivity. Accordingly, the resulting hybrid nanoarchitectures express superior electrocatalytic properties in terms of a low onset potential of only 45 mV, a small Tafel slope of 61 mV dec -1 as well as a long service life towards the HER, which make it quite competitive against bare MoS 2 quantum dots, MXene as well as binary MQD/RGO and MQD/MXene electrocatalysts., (© 2024 Wiley-VCH GmbH.)

Wood, as a renewable material, has been regarded as an emerging substrate for self-supporting electrodes in large-scale water electrolysis due to numerous merits such as rich pore structure, abundant hydroxyl groups, etc. However, poor conductivity of wood can greatly suppress the performance of wood-based electrodes. Carbonization process can improve wood's conductivity, but the loss of hydroxyl groups and the required high energy consumption are the drawbacks of such a process. Here, a facile strategy is developed to prepare pristine wood-supported electrode (Ni-NiP/W) for enhanced hydrogen evolution reaction (HER); this improves electrical conductivity of wood while retaining its excellent intrinsic properties. The preparation process involves the deposition of copper on the untreated wood followed with the loading of Ni-NiP catalyst at room temperature. Encouragingly, the Ni-NiP/W exhibits conductive and inherited pristine wood's superhydrophilic and superaerophobic properties, that effectively boost mass and charge transfer. It demonstrates high activity and excellent stability in acidic, alkali, and seawater conditions as well as high current densities of up to 2000 mA cm -2 ; particularly a record-low HER overpotential of 206 mV in acidic conditions at 1000 mA cm -2 . This work fully unlocks the admiring potential of pristine wood as superior substrate for high-performance electrochemical electrodes., (© 2024 Wiley‐VCH GmbH.)

High-efficiency and low-cost catalysts for oxygen evolution reaction (OER) are critical for electrochemical water splitting to generate hydrogen, which is a clean fuel for sustainable energy conversion and storage. Among the emerging OER catalysts, transition metal dichalcogenides have exhibited superior activity compared to commercial standards such as RuO 2 , but inferior stability due to uncontrolled restructuring with OER. In this study, we create bimetallic sulfide catalysts by adapting the atomic ratio of Ni and Co in Co x Ni 1-x S y electrocatalysts to investigate the intricate restructuring processes. Surface-sensitive X-ray photoelectron spectroscopy and bulk-sensitive X-ray absorption spectroscopy confirmed the favorable restructuring of transition metal sulfide material following OER processes. Our results indicate that a small amount of Ni substitution can reshape the Co local electronic structure, which regulates the restructuring process to optimize the balance between OER activity and stability. This work represents a significant advancement in the development of efficient and noble metal-free OER electrocatalysts through a doping-regulated restructuring approach., (© 2024 Wiley-VCH GmbH.)

Regulating competitive reaction pathways to direct the selectivity of electrochemical CO 2 reduction reaction toward a desired product is crucial but remains challenging. Herein, switching product from HCOOH to CO is achieved by incorporating Sb element into the CuS, in which the Cu-S ionic bond is coupled with S-Sb covalent bond through bridging S atoms that elongates the Cu-S bond from 2.24 Å to 2.30 Å. Consequently, CuS with a shorter Cu-S bond exhibited a high selectivity for producing HCOOH, with a maximum Faradaic efficiency (FE) of 72 %. Conversely, Cu 3 SbS 4 characterized by an elongated Cu-S bond exhibited the most pronounced production of CO with a maximum FE of 60 %. In situ spectroscopy combined with density functional theory calculations revealed that the altered Cu-S bond length and local coordination environment make the *HCOO binding energy weaker on Cu 3 SbS 4 compared to that on CuS. Notably, a volcano-shaped correlation between the Cu-S bond length and adsorption strength of *COOH indicates that Cu-S in Cu 3 SbS 4 as double-active sites facilitates the adsorption of *COOH, and thus results in the high selectivity of Cu 3 SbS 4 toward CO., (© 2024 Wiley-VCH GmbH.)

This study aims to explore the n-FeO and p-α-Fe 2 O 3 semiconductor nanoparticles in hydrogen (HER) and oxygen (OER) evolution reactions and a combined full cell electrocatalyst system to electrolyze the water. We have observed a distinct electrocatalytic performance for both HER and OER by tuning the interplay between iron oxidation states Fe 2+ and Fe 3+ and utilizing phase-transformed iron oxide nanoparticles (NPs). The Fe 2+ rich n-FeO NPs exhibited superior HER performance compared to p-α-Fe 2 O 3 and Fe(OH) x NPs, which is attributed to the enhancement in n-type semiconducting nature under HER potential, facilitating the electron transfer for the reduction in H + ions. In contrast, p-α-Fe 2 O 3 NPs demonstrated excellent OER activity. An H-cell constructed using n-FeO||p-α-Fe 2 O 3 NPs as cathode and anode achieved a cell voltage of 1.87 V at a current density of 50 mA/cm 2 . The cell exhibited remarkable stability after 30 h of activation and maintained the high current density of 100 mA/cm 2 for 80 h with a negligible increase in cell voltage. This work highlights the semiconducting properties of n-FeO and p-α-Fe 2 O 3 for the electrochemical water splitting system using the band bending phenomenon under the applied potential.

Electrochemiluminescence (ECL) is a powerful tool for clinical diagnosis due to its exceptional sensitivity. However, the standard tripropylamine (TPrA) coreactant for Ru(bpy) 3 Cl 2 , the most widely studied and used ECL system, is highly toxic. Despite extensive research on alternative coreactants, they often fall short in poor efficiency. From a reaction kinetics perspective, accelerating electrooxidation rate of Ru(bpy) 3 Cl 2 is an essential way to compensate the efficiency limitation of coreactants, but is rarely reported. Here, a hybrid electrocatalyst@coreactant dots for the ECL of Ru(bpy) 3 Cl 2 is reported. The as-prepared WSe 2 @bovine serum albumin (WSe 2 @BSA) dots is biocompatible, and demonstrate dual functions, i.e., the BSA shell works as a coreactant, meanwhile, the WSe 2 core effectively catalyzes Ru(bpy) 3 Cl 2 oxidation. As a result, WSe 2 @BSA dots exhibit an exceptionally high efficiency comparable to TPrA for the ECL of Ru(bpy) 3 Cl 2 . In addition, the procedure for synthesizing WSe 2 @BSA dots is facile (room temperature, atmospheric conditions), rapid (5 min), and scalable (for millions of bioassays). A biosensor utilizing WSe 2 @BSA dots shows promise for highly sensitive detecting glypican-3 in clinical liver cancer serum samples, especially for alpha-fetoprotein-negative patients. This work opens a new avenue for developing a highly efficient ECL system for biosensing and clinical diagnosis., (© 2024 Wiley‐VCH GmbH.)