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The emerging high entropy oxide (HEO) with homogenously distributed multicomponent featuring great adjustability of composition and electronic structure shows attractive electrocatalyst performance. Herein, the SO 4 2--modified (Fe 0.2 Co 0.2 Ni 0.2 Cr 0.2 Mn 0.2) 3 O 4 grown on the hollow carbon sphere (HCS) has been prepared using a microwave-solvothermal strategy. The introduction of thioacetamide during the formation of HEO leads to the in-situ generation of SO 4 2− on the surface of HEO, which not only drives surface morphology and crystal structure evolution to expose more electrochemical active sites, but also intensifies surface reconstruction, including the formation of more hypervalent active metal ions, and the reduction of the reconstruction potential, thus improving the catalytic activity. The amorphous high-entropy structure with unsaturated coordination encourages more active sites generation. The HCS carriers effectively disperse the HEOs and promote gas release and electron transfer. As a return, the SO 4 2--modified HEO/HCS shows decreased charge transfer impedance and improved electrochemical active surface areas. The catalyst with the optimal S content exhibits a low overpotential of 237 mV at 10 mA cm−2 and Tafel slope of 40.38 mV∙dec‍‍‍-‍1 in 1 M KOH, as well as outstanding durability in 80 h. This work provides a comprehensive design route for the high-efficient high entropy electrocatalyst for OER. [Display omitted] • The SO 4 2-modified (FeCoNiCrMn) 3 O 4 /HCS is prepared using microwave-solvothermal strategy. • The SO 4 2− drives morphology/structure evolution, intensifies surface reconstruction. • The HEO-S1/HCS exhibits a low overpotential of 237 mV at 10 mA cm−2 as well as excellent durability. [ABSTRACT FROM AUTHOR]

The study focuses on the development and optimization of (Ni 87 Fe 4 Cr 9) 78 Si 8 B 14 amorphous ribbons as self-supported electro-catalysts for oxygen evolution reaction (OER) and methanol oxidation reaction (MOR). Electro-catalytically active nano α-Ni(OH) 2 phase (5–10nm) was generated in the amorphous ribbon surface through potentiostatic cathodic corrosion for different time intervals (0–120 min). The X-ray diffraction and scanning electron microscopy results shows the favourable occurrence of dense nanocrystallization of α-Ni(OH) 2 between 45 and 90 min of corrosion time. For OER in 1 M KOH, the 60-min surface modified ribbon exhibits an overpotential of 295 mV at 10 mA/cm2 current density and tafel slope of 51 mV dec−1. In case of MOR in 1 M KOH +1 M MeOH, the 90-min corroded ribbon shows lowest potential of 1.38 V vs RHE, at 10 mA/cm2 and tafel slope of 34 mV dec−1. In addition to superior electro-catalytic activity, the optimal surface-modified ribbons show superior long-term stability for OER and MOR studies, indicating its potential application in hydrogen generation and direct methanol fuel cell. [Display omitted] • Surface modified amorphous ribbon improves the electrocatalytic OER and MOR. • Catalytically active Nickel oxo/hydroxo sites are formed by Cathodic corrosion. • XPS of Ni2p suggests formation of oxygenated nickel species in corroded ribbon. • Optimized sample shows an overpotential of 295 mV at 10 mA/cm2 for OER. • Low onset in MOR (1.36 V vs RHE) widens its application in DMFC and H 2 generation. [ABSTRACT FROM AUTHOR]

Efficient hydrogen production via anion exchange membrane water electrolysis depends on hydrogen evolution reaction (HER) electrocatalysts with excellent kinetics in alkaline electrolytes. Amorphous alloys offer enhanced electrochemical properties and improved corrosion resistance, making them attractive candidates. Among these, the bimetallic nickel molybdenum (NiMo) alloy stands out as one of the most active transition-metal-based HER electrocatalysts, available in both amorphous and crystalline forms. This study investigates the influence of thermal annealing temperature in a reducing environment on the phase change and electrochemical properties of hydrothermally grown 1-dimensional (1D) NiMo nanorods. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) revealed that lower annealing temperatures resulted in a mixed amorphous and crystalline phase of NiMo, while higher temperatures led to increased crystallinity and a decrease in the amorphous fraction. Electrochemical analysis indicates that the amorphous NiMo annealed at 400 °C exhibits overpotentials as low as 31 and 115 mV at 10 and 100 mA cm−2, respectively, outperforming several similar electrocatalysts reported in the literature. This enhanced activity is attributed to improved electron and mass transport, along with increased exposure of active sites in the amorphous phase. Thus, there is a clear relationship between annealing conditions and the formation of amorphous NiMo, which exhibits excellent HER properties and durability. • Amorphous-crystalline NiMo alloy enhances HER kinetics in alkaline electrolytes. • Lower annealing temperatures yield amorphous characteristics of NiMo with superior HER activity. • NiMo annealed at 400 °C achieves 31 mV overpotential at 10 mA cm−2. • Amorphous state boosts electron transport and active site exposure. • Tailored annealing links to NiMo's excellent HER properties and durability. [ABSTRACT FROM AUTHOR]

Porous one-dimensional Pt-based alloys with outstanding specific surface areas, short electron transport paths, and accessible Pt atoms are potential electrocatalysts for methanol oxidation reaction (MOR); however, their simple one-step synthesis for MOR remains a challenge. In this study, a simple one-step method is presented for the rational fabrication of PtPb porous nanowires (PNWs) by the direct autoclave of binary metal precursors in the mixed solvent of ethylene glycol and N,N -dimethylformamide at 170 °C. The formation of PtPb PNWs is driven by the autocatalytic and Ostwald ripening growth mechanism with the assistance of ethylene glycol and N,N -dimethylformamide as a solvent, in situ template, and reducing agent. This method forms PtPb porous ultra-long (∼1.5 μm) neural PNWs with an average width of 20 nm enriched with abundant pores (5–10 nm), high Pb content (29 wt%), and decreased d-band level of Pt. These unique structural features enhanced the MOR mass (specific) activity of PtPb PNWs of 4.39 mA/μg Pt (49.3 mA/cm2) by 4.5 (9.6) and 5.5 (35.0) times than those of Pt PNWs and Pt/C catalyst, respectively besides higher durability and CO-tolerance. The MOR activity of PtPb PNWs was among the highest reported binary porous Pt-based catalysts, which may promote the preparation of other Pt alloys PNWs for MOR. [Display omitted] • Porous PtPb neural nanowires (PNWs) were prepared by a simple one-step method. • The formation mechanism of PtPb PNWs was underlined using various analyses. • The methanol oxidation performance of PtPb PNWs was superior to other PtPb. • The mass activity of PtPb PNWs was higher than Pt PNWs and Pt/C catalysts. [ABSTRACT FROM AUTHOR]

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 CO2 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 CO2RR 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 CO2 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. [ABSTRACT FROM AUTHOR]

ABSTRACT Climate change is seen as a crucial environmental dilemma that humanity will confront in the upcoming decade. For this purpose, the solvothermal‐assisted technique is used to create metal–organic frameworks (MOFs), which are porous materials characterized by strong connections between organic ligands and metal ions. The MOF discussed here contains cobalt as the metal node and a linker derived from 2‐aminobenzoic acid and terephthalaldehyde. The prepared powder underwent analysis using various techniques including Fourier‐transform infrared spectroscopy (FT‐IR), powder X‐ray diffraction (PXRD), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) surface area measurement, and thermal analysis. BET analysis revealed a surface area of 1587.06 m2/g, a total pore volume of 0.86394 cc/g, and an average pore size of 1.088 nm. The RGO@Co‐MOF prepared was utilized to evaluate water splitting efficiency, demonstrating favorable catalytic activity like most reported modified MOF catalysts under low current density conditions of 10 mA/cm2. [ABSTRACT FROM AUTHOR]

Developing sustainable and highly effective electrocatalysts for the oxygen evolution reaction (OER) is a significant research target for precise custody of water splitting to fulfill worldwide energy demands. This study focuses on the fabrication of SrTiO 3 /rGO-based composite via a solvothermal technique, which works as an electrocatalyst for evaluating the efficiency of OER in alkaline media. The material displays outstanding OER efficacy in 1 M KOH solution with its cubic structure validated by the X-ray diffraction (XRD) study. The electrochemical study reveals that the SrTiO 3 /rGO composite has a minimal overpotential (222 mV) compared to SrTiO 3 (289 mV) and the commercial catalyst RuO 2 (367 mV). The SrTiO 3 /rGO composite also has a minimal Tafel plot gradient of 37 mV dec−1 whereas RuO 2 has a Tafel value of 72 mV dec−1. The current material has superior properties compared to RuO 2 , a commercial catalyst for the OER. The SrTiO 3 /rGO composite shows exceptional stability for 40 h. The low conductivity of oxygen-deficient SrTiO 3 perovskite can be improved by incorporating carbon-based rGO into it, as demonstrated by the minimal Rct (0.07 Ω) obtained from electrochemical impedance spectroscopy (EIS) analysis and an enlarged surface area of 250 cm2, as evidenced by electrochemical surface area (ECSA). Therefore, our research indicates that a particular morphology of metal oxide can improve the efficiency of electrocatalysis when combined with reduced graphene oxide (rGO), suggesting its potential for generating effective and environmentally friendly energy. Hence, these findings may improve the smooth passage of electrons and provide a novel perspective to function as an adequate substitute for RuO 2 , a commercial catalyst. [ABSTRACT FROM AUTHOR]

Engineering metal‐oxygen (M‒O) interactions for catalyzing oxygen evolution reaction (OER) by tuning the coordination geometry of metal sites is crucial for improving catalytic performance, which remains unexplored, especially in structurally diverse phosphate‐based catalysts. Herein, two NaCoPO4 (NCP) polymorphs with distinct metal coordinations: orthorhombic‐Pnma (CoO6) and hexagonal‐P65 (CoO4) denoted as O‐NCP and H‐NCP, respectively are synthesized through unique quenching‐based synthesis, to investigate the impact of coordination geometry on M‒O covalency and OER performance. The CoO4 (H‐NCP) polymorph delivered superior OER activity with low overpotential at 10 mA cm−2 (η10 = 303 mV) and long‐term stability than CoO6‐based O‐NCP. Spectroscopic and computational studies linked the superior activity of CoO4 to higher Co‒O covalency, enhanced metal electronic states near the Fermi level, and improved electrochemical reconstruction. Further, M‒O covalency regulated OER mechanism, where high‐covalent CoO4 follows conventional concerted proton‐electron transfer pathway, while CoO6 entails a non‐concerted pathway, where the lattice oxygen participation remains unfavorable due to downshifted O 2p band center. Further, OER‐active tetrahedral metal is demonstrated in a high‐entropy catalyst requiring lower η10 of ≈284 mV. This study unlocks a unique strategy for designing next‐generation OER catalysts with superior activity and durability, harnessing the interplay between metal coordination and metal‐oxygen covalency. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) is an important raw material in the chemical industry, but the synthesis of NH3 by the traditional Haber‐Bosch process will increase the carbon footprint. Therefore, it is necessary to develop sustainable routes for NH3 production. New NH3 production schemes, including nitrogen reduction (N2RR), nitrite reduction (NO2RR), and nitrate reduction (NO3RR), have been proposed. Porphyrins and phthalocyanines are macrocyclic compounds with a central metal ion coordinated with nitrogen. The metal centers in these catalysts play a crucial role in binding and activating nitrogen, nitrite, and nitrate. Their unique structure allows for effective electron transfer and catalytic activation in NH3 synthesis. Recently, metal porphyrin and phthalocyanine based catalysts have been demonstrated to be efficient in catalyzing N2RR, NO2RR, and NO3RR. Unfortunately, there is no review focusing on such macrocyclic catalysts for the electrocatalytic synthesis of NH3. In this review, we discuss the electrocatalytic reduction performances and summarize the key factors and reaction mechanisms that affect the catalytic performance of metal porphyrin and phthalocyanine based catalyst systems. This review helps to design more effective new electrocatalysts for NH3 synthesis. [ABSTRACT FROM AUTHOR]

Pyrolytic single Fe atom‐nitrogen‐carbon materials (Fe−N−C) and their derivatives are excellent catalysts for electrochemical oxygen reduction reactions. However, they exhibit poor oxygen evolution reaction (OER) activity due to non‐optimal Fe−O* bonding. This limitation is overcome via electronic structure modulation (i. e., tuning the heteroatom type, concentration, and location within Fe's n≥1 coordination sphere). However, the methods used are complex and energy‐intensive (i. e., 1000 to 1200 °C) raising concerns about reproducibility and cost. This study introduces a method for synthesizing nonpyrolytic Fe−N−C/Fe2O3 composites with similar electronic structure modulation as pyrolytic Fe−N−C and OER activity akin to commercial RuO2. The methodology involves doping low‐melting hydrated Fe‐salts in electrospun polyacrylonitrile nanofiber to catalyze its transformation into conjugated pyridinic‐N‐rich graphite‐like sheets (i. e., N−C) at 300 °C. N−C chelate effectively with oxygen‐vacant (Ov)‐rich Fe atoms derived from Fe2O3 NPs resulting in Fe−N−C/Fe2O3 heterostructures. The Fe2O3 coupling effectively tunes Fe−N−C's electronic structure via Ov modulation. Consequently, the Fermi and d‐orbital energy levels are optimized leading to partial filling of the antibonding states, optimal Fe−O* bonding, high electrochemically active surface area, and OER activity. Because Fe−N−C /Fe2O3 is synthesized at 300 °C using well‐established techniques, its complexity and cost are favorable compared to pyrolytic Fe−N−C materials. [ABSTRACT FROM AUTHOR]

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 Ti3C2Tx MXene (Ti3C2Ox) is synthesized and deposited gold nanoparticles (Au NPs) onto it, forming a novel composite material, Au‐Ti3C2Ox. 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 H2SO4 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 Ti3C2Ox. This work provides a surface modification strategy to fully utilize the MXene surface and enhance the overall catalytic activity of MXene‐based catalysts. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 MoSe2, for the efficient electroreduction of dinitrogen to ammonia. The introduced Fe dopant significantly enhances nitrogen fixation activity of MoSe2. Furthermore, we constructed a heterostructure catalyst, the Fe‐MoSe2/Mo2C 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 MoSe2. This study presents a novel approach for designing bionic nitrogen fixation electrocatalysts. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru)‐ and iridium (Ir)‐based nanomaterials have always been regarded as efficient electrocatalysts for oxygen evolution reaction (OER) in acidic electrolytes. Herein, we develop a facile dodecylamine‐assisted hydrothermal synthesis for producing carbon‐supported IrRu alloy nanoparticles with controllable Ir/Ru ratios and ultrafine sizes towards high‐efficiency OER and overall water electrolysis. In this strategy, the dodecylamine that serves as a capping and reducing agent enables the final IrRu alloy nanoparticles to possess average sizes <3 nm and high degree of dispersion on carbon substrate. By combining high OER activity of Ru with high acidic robustness of Ir, the as‐prepared IrRu/C nanoparticles at a suitable Ir/Ru ratio of 1/3 show good activity and durability for the OER electrocatalysis and overall water splitting. In specific, the Ir1Ru3/C catalyst exhibits the lowest overpotential of 302 mV at the current density of 10 mA cm−2 and the highest mass activity of 120.5 mA mg−1 at 1.532 V for OER in 0.5 M H2SO4 electrolyte. In addition, a two‐electrode acidic electrolyzer assembled with Ir1Ru3/C at anode and commercial Pt/C at cathode (Pt/C|| Ir1Ru3/C) exhibits a low cell voltage of 1.44 V for achieving the current density of 10 mA cm−2, along with a satisfied 20h durability. [ABSTRACT FROM AUTHOR]

Among various strategies to enhance electrocatalytic activity, nanoporous structured electrodes have been widely utilized owing to their improved performance. Along with enlarged electrode surface, modified crystalline facets, and surface defects of nanoporous electrodes, recent studies have reported their unique electrocatalytic characteristics originating from the nanoconfined space, denoted as the nanoconfinement effect. Introducing nanoporous electrodes with controllable thickness made of indium tin oxide, an electrochemically inert material, has provided an optimal platform for analyzing the contribution of nanoporous structures to the catalytic effects. Nevertheless, the scope of reactants that has been studied based on this system so far is mostly limited to ferric/ferrous redox species in sulfate anion environment. Here, using the nanoporous indium tin oxide electrodes, we demonstrate the nanoconfinement effect toward the ferric/ferrous reaction in a different chemical environment that alters its electrokinetic characteristics compared to the previous studies. Furthermore, a complex multi‐electron transfer reaction of oxygen reduction is employed to explore the effects of nanoporous structure toward inner‐sphere reactions. Our work suggests that the nanoconfinement effects can be applied to a wider range of electrochemical reactions taking place in nanoporous electrodes. [ABSTRACT FROM AUTHOR]

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 NiCo2O4, 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 NiCo2O4 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 NiCo2O4 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. [ABSTRACT FROM AUTHOR]

Electrocatalytic oxidation of biomass‐derived 5‐hydroxymethylfurfural (HMF) presents a promising pathway for synthesizing the value‐added chemical, 2,5‐furandicarboxylic acid (FDCA). However, it is still lack of scalable strategies to fabricate electrocatalysts with high activity and selectivity. Herein, a bayberry‐like Ni@Ni3S2 core–shell catalyst is prepared via a spontaneous corrosion strategy for HMF electro‐oxidation. The Ni3S2 shells with abundant electron‐deficient Ni sites facilitate the generation of high‐valence Ni3+OOH active species. Additionally, the in situ oxidation of S2− to SO42− enhances the electron and proton transport capacity. Both high‐performance liquid chromatography (HPLC) and density functional theory (DFT) analyses reveal that Ni@Ni3S2 preferentially selects the 2,5‐dicarboxyfurylfuran (DFF) pathway due to the lower reaction energy barrier from HMF to DFF, and the rate‐determining step of DFF oxidation to generate 5‐formylfuran‐2‐carboxylic acid (FFCA) is significantly accelerated. Consequently, the yield of FDCA and Faraday efficiency are found to be 99.20% and 99.35%, respectively, and they still reach 88.79% and 90.33% after ten cycles, showing excellent stability. Moreover, a mass production of 13.97 g Ni@Ni3S2 is successfully synthesized using the spontaneous corrosion strategy. This work offers a valuable reference for designing scalable and high‐performance catalysts by manipulating reaction routes to achieve efficient biomass conversion. [ABSTRACT FROM AUTHOR]

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 O2 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. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) have recently attracted much attention in the scientific community as a prominent catalyst for oxygen evolution reaction (OER) because they are economical, extremely stable, and highly active. Literature on LDH alone and their hybrids for catalyzing water oxidation are readily available, but LDH catalyzing hydrogen evolution reaction (HER) is meager. Here, we synthesized Co/Al‐based LDH systems that efficiently perform as bifunctional electrocatalysts for both HER and OER. Exfoliation of this layered material via anion intercalation into a few layers further enhanced its activity. In this work, we reported the synthesis of Co/Al LDHs via coprecipitation followed by hydrothermal method and different surfactant‐functionalized LDHs (with anionic surfactant: SDS, cationic surfactant: CTAB, and nonionic surfactant: PEG 4000). SDS‐modified LDH (s LDH) showed notable stability and competent results in hydrogen evolution in addition to oxygen evolution. The exfoliation of s LDH caused enhancement in the high specific surface area about 6.8 times compared to pristine LDH, as evident from BET data. The onset potential for HER as obtained from the polarization curve for s LDH is −0.41 V versus RHE, with Tafel slope of 67.4 mV/dec. Similarly, OER onset potential and corresponding Tafel slope are 1.53 V versus RHE at 10 mA/cm2 and 90.2 mV/dec, respectively. [ABSTRACT FROM AUTHOR]

Efforts are underway to develop highly active catalysts to reduce the high overpotential of the oxygen evolution reaction (OER). Metal–organic frameworks or coordination polymers are promising candidates because of their tunable structures and high surface areas. In this study, Nickel and Cobalt trans‐cinnamate (t‐ca) were synthesized via a hydrothermal method. Their structures were analyzed and found to be isostructural. Both complexes exhibited superior electrocatalytic properties in the OER compared to those of IrO2, with overpotentials of 373 and 390 mV and Tafel slopes of 58 and 66 mV/dec. These excellent characteristics were attributed to the electron delocalization of the metal centers via interactions with π‐π delocalized organic ligands. Ni t‐ca, with stronger ligand interactions, displayed an enhanced OER catalytic performance, emphasizing the importance of metal–ligand interactions and suggesting that further exploration of diverse π–π delocalized organic ligands and metal centers may lead to further advancements in electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Electrochemical two‐electron water oxidation reaction (2e− WOR) driven by renewable energy offers an attractive route to produce H2O2, while the corresponding electrocatalyst still requires further improvement for the activity, selectivity, and the resulting H2O2 yield. Surface‐interface engineering of electrocatalysts has great potential to advance 2e− WOR performance. This review provides a succinct yet comprehensive insight into the functional mechanisms of surface‐interfacial properties affecting 2e− WOR performance on electrocatalyst. The Gibbs free energy theoretical framework related to surface electronic structure and interfacial reactive kinetics mechanism related to electrolyte, electrode–electrolyte interface structure, and interfacial microenvironment properties are firstly discussed. Afterward, various surface‐interface engineering strategies toward high performance electrocatalysts including the regulation of surface electronic structure, the electrode–electrolyte interface structure, and the interfacial microenvironment have been overviewed. Rational manipulations of the above surface‐interfacial engineering strategies are critical to design highly efficient 2e− WOR electrocatalysts, leading to the development of the green H2O2 production. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur (Li‐S) batteries, with their high theoretical energy density and cost‐effectiveness, have become one of the most promising next‐generation energy storage devices. However, they still face challenges such as the “shuttle effect” caused by the dissolution of polysulfide intermediates and the slow sulfur conversion kinetics. In this study, based on the Co7Fe3 alloy catalyst, additional Co metal is introduced to form a Co7Fe3Co catalyst with a heterostructure through a simple heat treatment process. This catalyst is incorporated into Ketjenblack (KB) to form a sulfur‐infused cathode material (designated as S/KB/Co7Fe3Co). Li‐S batteries using S/KB/Co7Fe3Co as the cathode demonstrate outstanding electrochemical performance, maintaining a reversible specific capacity of over 500 mAh g−1 after 1000 cycles at a current density of 1 C, with a capacity decay rate of 0.046% per cycle. DFT theoretical calculations and experimental results both reveal that the introduction of additional Co effectively regulates the d‐band center of the material, enhancing the adsorption of polysulfide intermediates by Co7Fe3Co and promoting bidirectional catalytic sulfur conversion. This work highlights the importance of the simple construction of heterostructured catalytic materials and their role in improving the performance of Li‐S batteries. [ABSTRACT FROM AUTHOR]

One of the most significant steps for the widespread application of Proton Exchange Membrane Fuel Cells (PEMFC) is the development of an efficient and corrosion-resistant electrocatalyst for Hydrogen Oxidation Reaction (HOR). To achieve an enhanced electrocatalytic activity towards HOR, we developed a carbon-free electrocatalyst that performs on par with the Pt/C commercial-based catalyst. Pt nanoparticles dispersed on hydrogenated WO 3 surfaces were synthesized and experimentally shown to be an efficient HOR electrocatalyst. Furthermore, different characterizations and electrochemical studies validate the performances of all the hydrogenated samples. Pt/a-WO 3 /H400, hydrogenated at 400 °C, exhibits excellent electrocatalytic activity in terms of onset potential, limiting current density, and electrochemical surface area (ECSA). The membrane electrode assembly (MEA) was fabricated, and its single-cell performance was carried out using Pt/a-WO 3 /H300, Pt/a-WO 3 /H400, and Pt/a-WO 3 /H500 at the anode with Pt loading of 0.125 mg/cm2. The single-cell performance of Pt/a-WO 3 /H400 as anode electrocatalyst has the highest power density (540 mW/cm2) at 50 °C and high durability, compared to Pt/C. The enhanced electrocatalytic performance is attributed to the synergistic catalytic effect between Pt nanoparticles and the WO 3-x interface. This occurs due to the preferential orientation of the highly active (002) facet and the creation of an optimum amount of oxygen vacancies due to the hydrogenation impact. • a-WO 3 hydrogenated at different temperatures (300 °C, 400 °C, 500 °C) synthesized. • Pt/a-WO 3 /H400, hydrogenated at 400 °C, have the highest electrocatalytic activity. • Pt/a-WO 3 /H400 shows maximum power density 540 mWcm−2 at Pt loading 0.125 mgcm−2. • Presence of optimum oxygen vacancies in the a-WO 3 /H400 hydrogenated surface. • Robust SMSI interaction between Pt and a-WO 3 /H400 interface observed. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrogen energy is considered a potential solution to the energy crisis and environmental pollution concerns. Pure hydrogen can be produced from electrochemical water splitting, however, the oxygen evolution reaction (OER) is the primary obstacle due to its sluggish reaction kinetics. Introducing methanol oxidation is one possible solution to replace OER for water splitting to produce hydrogen as an energy source. In this article, a NiCo₂O₄-based wool-ball electrocatalyst was prepared via a solvothermal process followed by annealing. The catalyst showed high purity and a wool-ball structure, where the threads are arranged in different patterns and composed of sub-nano-sized spheres. The catalyst exhibited an excellent response to oxidation reactions and reduced severely the potential for 250 mV, when 1.17 mM of methanol was introduced into a 1 M KOH solution. The catalyst also demonstrated good performance for the hydrogen evolution reaction (HER), however, there was a reduction in performance in the presence of methanol. This might be due to the formation of a methanol layer that inhibits the HER in the KOH solution, as methanol does not participate in HER. This resistance was confirmed with electrochemical impedance spectroscopy (EIS) and electrochemical surface area (ECSA) measurements, where the ECSA value in KOH was 4.10, which reduced to 2.63 in the presence of methanol. The catalyst exhibited excellent stability for both HER and methanol oxidation reaction (MOR) over a long duration of 3600 s. • The NiCo 2 O 4 reduce the overpotential for 240 mV. • NiCo 2 O 4 based wool-ball are prepared via solvothermal follow by annealing method. • The catalyst showed excellent stability for 3600 s and high ECSA of 12.88 mF/cm2. • The catalyst follow Volmer-Heyrovsky mechanism as per Tafel slope. [ABSTRACT FROM AUTHOR]

Developing low-cost, high-performance oxygen reduction reaction (ORR) catalysts is crucial for the commercialization of fuel cells and zinc-air batteries. Herein, we report a lignin-derived Fe/N co-doped 3D porous carbon electrocatalyst Fe-NLC-1 as an alternative to commercial Pt/C catalysts, which was synthesized by a green and facile in situ carbonization strategy. Fe-NLC-1 exhibits higher oxygen reduction activity with a half-wave potential (E 1/2) of 0.90 V vs. RHE than commercial 20 wt% Pt/C (E 1/2 = 0.85 V) in the alkaline conditions, as well as excellent methanol tolerance and stability. Furthermore, the Zn-air battery loaded with Fe-NLC-1 exhibits a maximum power density of 125 mW cm−2, an open circuit voltage of 1.477 V, and stable discharge performance, which are comparable or even better than the commercial Pt/C. This study highlights the potential of biomass-derived porous carbon materials for the development of high-performance ORR electrocatalysts. [Display omitted] • Industrial waste lignosulfonate is used to prepare an oxygen reduction catalyst. • The precursor of the porous carbon material is prepared using an in-situ template method. • Fe-NLC-1 with a 3D porous structure has a high specific surface area and excellent ORR performance. [ABSTRACT FROM AUTHOR]

The climate crisis has become the most serious concern of human beings and environments worldwide in the 21st century. Global concerns about cancer epidemiology mainly originate from anthropogenic activities, particularly fossil-based operations. A key solution to this problem is the use of fuel cells—devices—capable of the direct conversion of fuel chemical energies like urea into electricity. To make their commercialization reasonable, one of the problems that needs to be solved is the development of anodic materials. The majority of investigations on urea oxidation are based on nickel, but its inadequate activity limits the efficiency of these devices. In this work, we propose and synthesize a Ni-Cu-Fe ternary electrocatalyst for urea oxidation through a fast and facile electrodeposition method. The properties of the synthesized material are examined by Scanning Electron Microscopy (SEM) conjugated with Energy Dispersive X-ray Spectroscopy (EDS), Transmission Electron Microscopy (TEM), and X-ray Diffraction (XRD). Its electrochemical properties were also examined in a 1 M KOH solution with and without 0.15 M urea. We found that the prepared powder is active in the electro-oxidation of urea, with 1.65 Vvs RHE required for a current density of 10 mA cm−2 and a stable potential of 2.38 Vvs RHE required for 3 h of polarization at 10 mA cm−2. [ABSTRACT FROM AUTHOR]

The oxygen reduction reaction (ORR) has a crucial impact on the energy conversion efficiency and the performance of fuel cells, it is urgent to deliver low‐cost efficient ORR catalysts for the aim to scale up the utilization of fuel cells. In this study, three oxamidate copper(II) complexes [Cu2(trans‐L)(H2O)2(ClO4)2]·2H2O (Cuox), [Cu2(cis‐L)(bpy)(ClO4)2]·CH3OH (Cuoxbpy), and [Cu2(cis‐L)(mebpy)(ClO4)](ClO4) (Cuoxmebpy) (L = N,N–bis(2–pyridylmethyl)oxamide, bpy = 2,2′–bipyridine, and mebpy = 4,4′–dimethyl–2,2′–bipyridine) were prepared and characterized. The configuration of L varied from the trans form to the cis form as the bipyridines were introduced to the dicopper complex. The redox properties of three oxamidate copper(II) complexes and their catalytic activities for the ORR were studied in neutral aqueous solutions. The ORR onset potentials by Cuox, Cuoxbpy, and Cuoxmebpy were 0.417, 0.502, and 0.481 versus RHE, respectively. Three complexes homogeneously catalyzed the ORR to predominantly generate H2O2. A bimolecular catalytic pathway was proposed for the ORR mediated by Cuox, whereas a single‐molecular pathway was by Cuoxbpy and Cuoxmebpy. This work demonstrated that oxamidate metal complexes are promising ORR catalyst candidates provided that their electronic structures are appropriately tuned by altering the substituent on the organic ligands. [ABSTRACT FROM AUTHOR]

The potential of electrochemical water splitting to tackle energy and environmental issues has garnered substantial interest. In the present work, an effective ZnS/In2Te3 has been constructed by hydrothermal support on a stainless‐steel strip and explored for oxygen evolution. The addition of ZnS modifies the band structure of In2Te3 and enhances its specific conductivity and capacitance on an intrinsic level, making rapid ion transportation. The optimized ZnS/In2Te3 displayed efficient oxygen evolution reaction (OER) performance with an overpotential of 228 mV and a Tafel slope of 111 mV dec−1 with cyclic activity up to 1000 cycles in 1 M KOH solution. ZnS/In2Te3 has a large surface area (28 m3g−1) and a charge capacitance of (.037 mF), according to studies using Brunauer–Emmett–Teller and double‐layer capacitance. Combining several strategies improves overall electrochemical performance of ZnS/In2Te3, making it a promising option for use in state‐of‐the‐art OER. [ABSTRACT FROM AUTHOR]

Electronic configuration regulation is usually a feasible strategy to boost the electrocatalytic performance for transition metal oxides. Herein, a simple high-temperature annealing method is employed to optimize the electrocatalytic activity towards hydrogen evolution reaction (HER) for spinel oxide Co 3 O 4. The experimental results indicate the simple thermal treatment partially drives the structure reversal in spinel Co 3 O 4 , and it induces the redistribution of cobalt ions at tetrahedral and octahedral sites. Thereby, the electronic configuration regulation occurs, and the e g occupation of cobalt ions at octahedral sites increases up to 1, optimizing the HER reaction kinetics. The sample treated at 900 °C exhibits the highest activity, with overpotential of 335 mV at current density of 10 mA cm−2, and Tafel slope value of 99.3 mV dec−1. This work offers a new way of tuning the electronic configuration in spinel oxides to boost HER electrocatalytic activity. • A simple high-temperature annealing method was adopted to partially drive the structure reversal in Co 3 O 4. • Partial structure reversal can induce redistribution of cobalt ions, and effectively modulate electronic configuration. • Complex spinel exhibited better HER activity than that of normal spinel. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) exhibit considerable potential as a promising technology, particularly when addressing the challenge of replacing the costly Platinum (Pt) counter electrode (CE) with economically viable and chemically stable CE materials. This study examines the use of two-dimensional hexagonal-shaped nickel oxide nanosheets substituted with varying mol% of lithium (1, 3, and 5 %) (Li (1–5%)-NiO NSs) as the counter electrodes (CEs) for DSSCs. The facile hydrothermal method was employed for the preparation of NiO and Li (1–5 mol%)-NiO samples. The BET analysis of NiO and Li (1–5%)-NiO indicates that higher concentrations of Li1+ ions in Ni2+ ions sites lead to an increase in the overall surface area of NiO. This leads to an elevated number of exposed electrocatalytic active sites which resulted in enhancing the rate of reduction of I 3 − ions. The cyclic voltammetry (CV) result of 5 mol% of Li substituted NiO (5-LNO) shows outstanding electrocatalytic activity towards the redox reaction of I 3 − / I − redox mediator among the as-prepared CEs. The DSSCs assembled with 5-LNO CE show an excellent power conversion efficiency (η) of 5.84 % with short-circuit current (J s c) of 18.76 mAcm−2, and open-circuit voltage (V o c) of 0.80 V which is higher than Pt-based CE (η of 4.05 % with J s c of 10.16 mAcm−2, and V o c of 0.69 V). The DSSCs fabricated with 5-LNO CE exhibit excellent photovoltaic performance because of their high active surface area and enhanced electrical conductivity. The 5-LNO CE has low cost, significant electrocatalytic activity, less toxicity, and superior device efficiency than NiO, other Li (1–3%)-NiO, and Pt CEs, making it a suitable candidate for Pt-free DSSCs application. [ABSTRACT FROM AUTHOR]

3D turf-like materials, synthesized through the regulation of nitrogen-containing organic compounds, can significantly increase the effective electrochemical active surface area, thereby improving the mass transport ability of ORR and OER. Furthermore, high pyridinic-N doping can effectively enhance the intrinsic activity of catalyst. [Display omitted] 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. [ABSTRACT FROM AUTHOR]

We propose a double loading strategy to construct heterostructures of both Ag and AgP 2 (Ag-AgP 2 /Ni 2 P) on the surface of Ni 2 P. This is also the first application of AgP 2 in electrocatalytic hydrogen evolution reaction. [Display omitted] 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. [ABSTRACT FROM AUTHOR]

Using renewable energy for water splitting to produce hydrogen is a crucial step toward achieving the dual carbon goals. However, due to the lack of a clear understanding of the precise localization of catalytic active sites and the complex structural evolution of catalysts during actual reaction conditions, there is still a challenge to reveal the electrocatalytic reaction mechanism of water splitting. In situ electrochemical Raman characterization technique can dynamically monitor the structural evolution of catalysts in real time, reveal the dynamic structure‐performance relationship of catalysts during the reaction process, and explore the catalytic reaction mechanism. This paper focuses on reviewing the latest developments in in situ electrochemical Raman characterization technology in terms of active sites on catalyst surfaces, the behavior of interfacial water molecules, and the structure evolution of electrocatalysts. The future development prospect of advanced in situ electrochemical Raman technology is also prospected. [ABSTRACT FROM AUTHOR]

The glucose oxidation reaction (GOR) is a potential alternative to water oxidation because of its relatively low thermodynamic potential and the high availability of glucose. Herein, a FeCoO/N‐doped C electrode derived from metal–organic framework (MOF) materials is applied, which is synthesized in several steps through the controlled deposition of Fe–Co oxide nanocatalysts onto Co –N‐doped C nanofibers on a Ni foam substrate and demonstrate exceptional electrocatalytic activity for both the GOR and overall water splitting. Here, a bifunctional electrocatalyst derived from MOF, FeCoO/N‐doped C is reported, for glucose oxidation reaction (GOR) and hydrogen evolution reaction (HER). The MOF‐derived FeCoO/N‐doped C (+/‐) as a bifunctional electrocatalyst exhibits a cell voltage of 1.4 V for the GOR&HER, to reach a current density of 10 mA cm−2, which is 280 mV lower than that for the oxygen evolution reaction (OER)&HER (1.68 V). This study reveals that GOR is an energy‐efficient and affordable source of H2 and value‐added chemicals. [ABSTRACT FROM AUTHOR]

Developing cutting-edge catalysts for oxygen evolution reaction (OER) is crucial for enhancing the efficiency of water splitting. Spinel-type materials have gained recognition for their exceptional catalytic performance in OER activity. The excessive OER overpotential is the significant obstacle that hinders the use of spinel-type materials. In this work, polyaniline (PANI) was incorporated to significantly enhance the performance of spinel SnFe2O4 material by straightforward hydrothermal method. SnFe2O4@PANI catalyst demonstrated an impressive overpotential of 198 mV at 10 mA cm–2 and a 33 mV dec–1 Tafel slope with higher OER activity. The electrochemical surface area (ECSA) of SnFe2O4@PANI catalyst was determined to be 2348.53 cm2, with higher cyclic stability of 25 h after 5000th cycles with minimal impedance characteristics (Rct = 0.18 Ω). In addition, the findings showed that the inclusion of PANI led to expansion of the surface area to improve the conductivity, resulting in notable enhancement of the catalysts' OER activity. This modification has resulted in an improved OER catalyst, making it highly sought after for various applications in the water-splitting field. Highlights: SnFe2O4@PANI catalyst was synthesized through hydrothermal route for improved OER activity. The SnFe2O4@PANI catalyst displays a reduced overpotential of 198 mV and Tafel slope of 33 mVdec−1. SnFe2O4@PANI catalyst demonstrates remarkable cycling stability of 25 h. SnFe2O4@PANI catalyst exhibits significantly lower impedance of Rct = 0.18 Ω. [ABSTRACT FROM AUTHOR]

Hydrogen production from water splitting is considered the most environment-friendly and sustainable method to acquire energy. Alkaline water electrolysis has been widely employed for hydrogen production, but it is still challenging to prepare non-precious metals electrocatalysts to replace the noble-metal-based catalysts. Here we proposed electroless method to prepare a NiCoP nanocrystalline thin flim as efficient electrocatalysts. The morphology and mechanisms of the 45-minute alloy films deposited on Cu substrate were characterized by SEM, XRD, and XPS techniques, moreover, LSV, EIS, and CP were applied to analyze the electrochemical behavior. The nanocrystalline NiCoP45min alloy exhibits higher hydrogen evolution reaction (HER) activity than platinum sheet. An overpotential of -98 mV and a Tafel slope of 47.94 mV·dec−1 at 10 mA·cm−2 was achieved with the catalyst during HER in an alkaline medium. Additionally, its excellent catalytic activity is confirmed by a low Rt value 2.48 Ω. Remarkably, this catalyst also exhibits high HER stability for about 45 h in an alkaline electrolysic solution. [ABSTRACT FROM AUTHOR]

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Single‐atom catalysts (SACs) demonstrate high selectivity, maximal atom utilization, and unique active site configurations, establishing them as a rapidly expanding research field. Understanding the intrinsic relationship between structure and catalytic performance is crucial for the effective use of SACs in catalysis. However, providing a clear explanation of the coordination environment and intrinsic structural regulation of SACs remains a significant challenge for next‐generation renewable energy materials, especially in advanced oxidation and reduction processes critical for sustainable energy applications. This comprehensive review offers an in‐depth overview of the current progress and design of SACs, with a specific focus on precise synthesis, structural control, and the relationship between structure and performance. Furthermore, we elucidate the reaction mechanisms of various catalytic systems and the selective methods used to precisely synthesize and enhance catalytic reactions in the sustainable energy sector. Finally, this review explores the complex challenges in investigating and developing SACs and offers a perspective on solutions in advanced oxidation and reduction technologies for future research to overcome these challenges and achieve practical applications. [ABSTRACT FROM AUTHOR]

ABSTRACT Excessive usage of fossil fuels has led to significant depletion, creating an energy crisis and environmental concerns. This has prompted the creation of sustainable energy conversion systems. This study explores sol–gel incorporation of Sm‐doped MnTiO3 nanostructure, which exhibits OER activity. Different analytical techniques were used to assess the material's morphology, structure, and textural properties. BET analysis confirmed increased surface area (34 m2 g−1) of Sm‐doped MnTiO3 nanostructure, which enhanced OER performance. The electrochemical results showed that the fabricated doped nanostructure had a lower overpotential of 201 mV, resulting in a current density of roughly 10 mA cm−2 and a Tafel slope of 40 mV dec−1. In EIS analysis, a low Rct value of Sm‐doped MnTiO3 (0.20 Ω) compared with pure MnTiO3 (0.23 Ω) indicates highly efficient charge transfer and a faster faradaic reaction. Chronoamperometry and cyclic stability analyses of Sm‐doped MnTiO3 nanostructure demonstrate stability over 35 h. The fabricated nanostructure has remarkable electrochemical characteristics, making it a promising material for future applications in electrical and other areas. [ABSTRACT FROM AUTHOR]

Alloy catalyst is considered to be an important strategy to solve the shuttle effect and sluggish kinetics of lithium‐sulfur batteries (LSBs). However, the effect of the electronic structure of the alloy catalyst on the sulfur conversion process has not been effectively analyzed. In this paper, based on alloying strategy, the electronic structure of such a FeCoNi catalyst is regulated and optimized, and the sulfur adsorption configuration and catalytic conversion process are defined. The in situ Raman spectroscopy and the density functional theory (DFT) are employed to deeply understand the catalytic mechanism of such a sulfur conversion. A cell with FeCoNi modified separator delivers an ultra‐low capacity attenuation of 0.056% per cycle over 1000 cycles at 3 C. The outstanding anti‐self‐discharge performance of 8.1% over 7 days is also achieved. Furthermore, the obtained cell with a high sulfur loading of 9.7 mg cm−2 and lean electrolyte of 5.6 µL mgs−1 exhibits 81% capacity retention after 100 cycles, providing a research prospect for the practical application of lithium‐sulfur batteries. [ABSTRACT FROM AUTHOR]

High‐efficiency electrocatalysts play an important role in clean energy conversion technologies. Generally, electrocatalysts in different environments, including voltage, acid, and alkali electrolytes, are more susceptible to corrosion, which will induce structural and performance changes. Based on the latest achievements in the corrosion and protection of electrocatalysts in advanced energy technologies, this review mainly studies the application of various corrosion strategies to construct superior electrocatalysts, including chemical etching, metal corrosion transformation, and corrosion reconstruction, and their affecting factors are also appraised and summarized. To improve the stability of electrocatalysts, various corrosion inhibition strategies, such as carrier improvement and composition regulation accompanied by structure optimization, are reviewed. In addition, the application of catalyst corrosion in electrochemical energy technologies is examined from the perspective of the structure‐activity‐performance relationship. In the end, this article concludes the perspective and challenges of electrocatalyst corrosion in energy conversion and storage technologies. This article provides insights and directions for designing electrocatalysts with high efficiency and low corrosion, which is beneficial for developing corrosion chemistry for sustainable energy technologies. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of nitrate (NO3RR) holds great promise for environmentally friendly ammonia production. Tandem catalysis is a promising strategy for boosting the NO3RR and inhibiting side effects, but it is still challenged by lacking well‐designed catalysts to drive this catalytic process. Herein, the study develops the CuCo branched nanowires (CuCo NW) catalyst, which efficiently converts NO3− to NH3 on Co (111) and Cu (111) crystal facets through a tandem catalysis mechanism. The in situ grown CuCo NW on Cu foam demonstrates a remarkable Faraday efficiency of 90.3% at 1.0 A cm−2 and maintains stable operation for 200 h at 100 and 200 mA cm−2 in a flow reactor. Density functional theory calculations suggest that the initial absorption and subsequent deoxygenation of *NO3 on Co (111) leading to the formation of *NO2, followed by its transfer to Cu (111) and further conversion to *NH3, establish an optimal pathway by managing rate‐determining steps on individual surfaces for NO3RR. To showcase the practical application of the catalyst, the study further develops a scaling‐up prototype reactor for continuous ammonia production, realizing the gram‐level yield rate of 1474.09 mg h−1 and Faraday efficiency of 91.26% at practical‐level 20.0 A. [ABSTRACT FROM AUTHOR]

The development of high-performance oxygen evolution reaction (OER) electrocatalysts based on earth-abundant elements is of great significance for the production of hydrogen fuel through water electrolysis. Herein, defect rich NiO nanosheet arrays were synthesized on nickel foam (NF) by rapidly quenching NiO in Al salt solution at 0 °C and followed by partially etching Al in alkaline solution. With the approach, the quenching can simultaneously achieve the required surface metal doping and generation of abundant oxygen vacancies. Moreover, more active sites can be provided for OER due to the leaching of Al during the etching process. As a result, the quenching-etching surface engineering endows the NiO catalyst with the desired advantages, including high conductivity and large specific surface area. The as-obtained optimal electrode (72h Al–NiO/NF) with an etching time of 72 h exhibited much enhanced electrocatalytic activity towards OER in alkaline solution, which needs a low overpotential of 277 mV to achieve 10 mA cm−2 water oxidation current. Furthermore, the catalyst also showed a very low Tafel slope of 51.8 mV dec−1 and excellent durability. The synthesis of defect rich NiO nanosheets through the quenching-etching route confirms the importance of elaborate engineering of material surface for high-performance OER. • Defect rich NiO nanosheet arrays grown on NF were successfully fabricated by a quenching-etching surface engineering route. • The obtained electrode successfully combined the desired merits, including high conductivity and large specific surface area. • The as-obtained 72h Al–NiO/NF shows superior activity, favorable reaction kinetics and robust durability for OER in alkaline media. [ABSTRACT FROM AUTHOR]

One of the primary challenges encountered in durability of polymer electrolyte membrane fuel cells (PEMFCs) is the carbon support corrosion of the conventional Pt/C catalyst. To address this challenge, the carbon support is replaced with titanium-based ones in the present study. Pt/TiO 2 , Pt/TiO 2-x (Pt/Black TiO 2), and Pt/TiC catalysts are synthesized and their structural characteristics, electrochemical activity for the oxygen reduction reaction (ORR), and stability are investigated and evaluated in comparison with the conventional Pt/C catalyst. Based on structural analyses, it is observed that the Pt/TiC catalyst exhibits a high specific surface area (1050 cm2 mg−1) and proper electrical conductivity of the support (4.5 × 10⁻1 S cm−1). According to the electrochemical evaluations, the Pt/TiC catalyst demonstrates superior ORR activity in acidic media, with a higher half-wave potential (0.84 V RHE) and a lower Tafel slope (69 mV.dec⁻1). Furthermore, stability evaluations indicate that both Pt/TiC and Pt/TiO 2-x catalysts exhibit higher stability compared to the Pt/C catalyst. Finally, based on the results obtained from the fuel cell tests, the Pt/TiC catalyst demonstrates competitive performance under optimal operating conditions (maximum power density of 573 mW cm−2 and current density of 694 mA cm−2 at 0.6 V) despite the low cathode loading of 0.1 mg Pt /cm2. [Display omitted] • Durability of Pt/TiO 2 Pt/TiO 2-x , and Pt/TiC is evaluated using 10000 aging cycles. • Among the synthesized catalysts, Pt/TiC shows superior ORR activity and stability. • Pt/TiC as the cathode catalyst shows a proper performance at low Pt loading. [ABSTRACT FROM AUTHOR]

It is vital to develop non-precious metal materials as dual-functional hydrogen evolution reaction (HER) and urea oxidation reaction (UOR) catalysts for water splitting. Herein, cobalt vanadate (CVO) nano/microrods electrocatalysts have been successfully synthesized by combining the sol-gel and pyrolysis method for HER and UOR. CVO-500 with the pyrolysis temperature at 500 °C shows optimal catalytic activity toward HER and UOR, which just needs overpotentials of 91.4 and 53.6 mV at 10 mA/cm2, respectively. In addition, it displays surpassing stability for uninterrupted HER and UOR. The CVO-500 catalyst as the anode and cathode for overall urea electrolysis only requires the voltage of 1.51 V to deliver 10 mA/cm2 with excellent stability in 1.0 M KOH with 0.33 M urea solution. The results suggest that cobalt vanadate nano/microrods with considerable catalytic performance as high-efficiency dual-functional electrocatalyst is believed as promising candidate to replace precious materials. [Display omitted] • Cobalt vanadate electrocatalysts have been successfully synthesized by combining the sol-gel and pyrolysis method. • Cobalt vanadate with the pyrolysis temperature at 500 °C (CVO-500) presents even and regular nano/microrods morphology. • The optimal CVO-500 shows overpotentials of 91.4 and 119.6 mV at 10 mA/cm2 for HER and UOR, respectively. • CVO-500 possesses conspicuous durability during sustaining HER and UOR. • CVO-500 catalyst for overall urea electrolysis requires the voltage of 1.51 V to deliver 10 mA/cm2 with excellent stability. [ABSTRACT FROM AUTHOR]

This study is focused on the synthesis of the perovskite oxide materials, particularly Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ , using different synthetic approaches (sol-gel and co-precipitation techniques) and different complexing agents and fuels and their applications for electrochemical water splitting and fuel cells. Prepared perovskite oxide materials exhibits dual catalytic behaviour as it shows the catalytic activity toward the oxygen evolution and reduction reactions in alkaline solution. The Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ electrocatalyst exhibits remarkable efficiency and durability for the OER in basic electrolytes, with a Tafel slope of 70.38 mV/dec for Best catalyst. The best ORR activity observed for Ba 0.5 Sr 0.5 Co 0.8 Fe 0.2 O 3-δ synthesized using citric acid shows Tafel slope of 356.43 mV/dec. These oxide materials also show enhanced efficiency in capacitive applications. Additionally, the prepared perovskite oxide materials have been characterized by Powder X-ray diffraction, Le-Bail refinement, scanning electron microscopy, Energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy analysis, and high-resolution Transmission Electron Microscopy. Electrochemical techniques such as linear sweep voltammetry, cyclic voltammetry, and electrochemical impedance spectroscopy techniques were used to assess the catalytic performance of the prepared electrocatalysts in 0.1M KOH solution. [Display omitted] • Perovskite oxides were synthesized and characterized. • Characterization was done by SEM, TEM, XPS and PXRD. • The catalysts prepared were utilized as bifunctional electrocatalysts. • Bifunctional electrocatalysts display dual catalytic activity for both the OER and the ORR in an alkaline media. [ABSTRACT FROM AUTHOR]

In this study, we report on the tailored synthesis of nitrogen-(N)-doped carbon and iron-(Fe)-loaded N-doped carbon composites and their use for the oxygen evolution reaction (OER), hydrogen evolution reaction (HER), overall electrochemical water splitting, and supercapacitors. FE-SEM and HR-TEM analyses reveal that the developed composite material exhibits a core-shell structure with enhanced porosity upon Fe incorporation. By adjusting the ratio of Fe to N-doped carbon in the composites, it was identified that the catalyst 5Fe@NC demonstrates outstanding electrochemical activity alongside commendable stability. Specifically, the 5Fe@NC electrocatalyst achieves current densities of +10 mAcm−2 and -10 mAcm−2 in alkaline electrolyte with minimal overpotentials of 376 mV and 520 mV, respectively. Notably, impressive Tafel slopes of 84 mV/dec and 212 mV/dec for the OER and HER were obtained, indicating superior kinetic activity of the developed composite materials. As a supercapacitor, 5Fe@NC electrode material exhibits a measurable specific capacitance of 294 F/g at 0.5 A/g current density with excellent durability (78 % retention after 1000 charge-discharge cycles). Furthermore, we conducted assessments on stability, charge transfer resistance, and ECSA, yielding excellent outcomes. This work successfully demonstrates a highly effective dual-purpose electrocatalyst prepared from indole and furfural (heterocycles abundant in biomass), exhibiting excellent electrochemical activity and stability in facilitating HER and OER within alkaline electrolytes. Fabrication of N-doped carbon and Fe loaded N-doped carbon composite materials and their characterization. The developed electrocatalysts were used as working electrode for OER, HER, overall water splitting and supercapacitor to evaluate their activity as efficient electrode materials. [Display omitted] • Fabrication of Fe-encapsulated N-doped graphitic carbon composites. • 5Fe@NC electrocatalyst reveals excellent activities towards OER and HER in alkaline medium. • 5Fe@NC works as a bi-functional electrocatalyst for the overall water-splitting reaction. • 5Fe@NC shows excellent performance towards specific capacitance (294 F/g). [ABSTRACT FROM AUTHOR]

ABSTRACT The development of low‐cost, high‐efficiency, stable, and structurally adjustable electrocatalysts for hydrogen evolution reaction (HER) is of great significance for energy conversion. In this study, two new Cu(I) coordination polymers (CPs), formulated as {[Cu(L1)](PF6)·CH2Cl2}n (1) and {[Cu2(L2)1.5(PPh3)](PF6)2}n (2) (L1 = 1,3‐bis[1‐(pyridin‐3‐ylmethyl) ‐1H‐benzimidazol‐2‐yl]propane, L2 = 1,4‐bis[1‐(3‐pyridylmethyl)‐1H‐benzimidazol‐2‐yl]butane), were synthesized by interfacial diffusion method and characterized by single‐crystal x‐ray diffraction and IR and UV–Vis spectra. Structural analysis shows that the CP‐1 is a one‐dimensional chain structure, whereas the CP‐2 is a two‐dimensional layered structure, which is due to the different coordination modes of ligands L1 (bridging chelation) and L2 (bridging). The electrocatalytic activity for HER of Cu(I) CPs was studied by preparing modified glassy carbon electrodes (CP‐1/GCE and CP‐2/GCE). Electrochemical HER studies manifest that in 0.5 M H2SO4, the overpotential (η10298K) and Tafel slope (b 298K) are −769 mV and 173 mV dec−1 for CP‐1/GCE, −933 mV and 301 mV dec−1 for CP‐2/GCE, and −930 mV and 298 mV dec−1 for bare/GCE, respectively. The η10298K and b298K of CP‐1/GCE were significantly positive shifted and decreased compared with the bare/GCE, indicating that CP‐1/GCE has significant electrocatalytic activity and electrocatalytic HER activity order is CP‐1/GCE > CP‐2/GCE ≈ bare/GCE. This work provides an important reference for the application of non‐noble metal CPs in the field of electrocatalysis. [ABSTRACT FROM AUTHOR]

In recent times, perovskite oxides have recognized to be an ideal alternative to platinum‐based oxygen reduction reaction (ORR) electrocatalysts due to their excellent stability, cost‐effectiveness, and tailorable properties. Herein, an ABO3 type LaFeO3 perovskite was doped at its B‐site to form electrochemically active LaFeB′O6 (B′=Cr, Zn, Co) by one‐pot hydrothermal synthesis process. Due to the synergistic effects of increased surface area and electrochemically active sites, Cr‐doped LaFeO3 largely improves the mass transfer kinetics for ORR in both conditions, alkaline (0.1 M KOH) and acidic (0.5 M H2SO4) with a positive onset Eon of 0.80 and 0.81 V (vs Ag/AgCl). Similarly, a half‐wave (E1/2) potential of 0.68 and 0.63 V (vs Ag/AgCl), which was comparable to the commercial 20 % Pt/C. Moreover, the La‐based perovskites were able to catalyze ORR with an electron transfer number (n)>3.6 signifying the superior 4‐electron pathway. Doped and undoped LaFeO3 exhibited remarkable stability in the chronoamperometry studies with a relative current of 92–95 % sustained over 8 h. Additionally, the La‐based electrocatalysts was unaffected by the crossover effect of methanol in both acidic and basic conditions, contrary to the commercial 20 % Pt/C. The present work serves as a useful strategy to maximize the efficiency and reliability in perovskites for energy‐related electrocatalytic applications and for alternative fuel generation. [ABSTRACT FROM AUTHOR]

Electrocatalysts for the oxygen evolution process must be both active and stable in order to make hydrogen from water using renewable power. Nitrogen‐doped carbon layer coated cobalt manganate particles were synthesized on carbon cloth using calcination method. The catalysts exhibited small particle sizes and graphitized carbon layer that covered the cobalt manganate, facilitating electron flow. Moreover, the nitrogen‐doped carbon layer enhanced the oxygen evolution reaction (OER) rate by reducing the potential required for surface reconstruction and optimizing electron distribution on the cobalt manganate surface. This electrocatalyst demonstrated a current density of 100 mA/cm2 at 1.56 V vs. RHE. Thus, this electrocatalyst shows promise as a novel OER catalyst for water oxidation in acidic aqueous solutions. [ABSTRACT FROM AUTHOR]