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Developing new forms of flexible zinc–air (Zn–air) batteries is crucial to economic growth. Nevertheless, the absence of an oxygen evolution reaction catalyst with high catalytic efficiency and low-cost causes instability of Zn–air battery cycling and economic unviability, respectively. In this paper, a leaf-like N-doped carbon structure with CoS2 nanoparticles self-supported on carbon fiber paper (CoS2-CZ@CFP) was developed as an air electrode for Zn–air batteries, which not only uses nonprecious metal elements, but also has a self-supporting configuration, enhancing the contact between the catalyst and electrode while facilitating the transfer of electrons. Sulfur as the source gas was introduced into Co-doped metal–organic skeletons (Co-ZIFs) anchored on carbon fiber paper (CFP) for in situ vulcanizing transition metal Co, which successfully ensures the uniform distribution of sulfide particles in the carbon matrix, hence enriching active catalyst sites. The CoS2-CZ@CFP demonstrated an overpotential of 1.611 V at J = 50 mA cm−2, superior to RuO2@CFP (1.814 V). A Zn–air battery fabricated using the synthesized CoS2-CZ@CFP exhibited an extended life cycle of 117 h. This research paves the way for a novel method of designing self-supporting configurations of sulfides and carbon matrix composites as promising air electrodes applicable to Zn–air batteries. [ABSTRACT FROM AUTHOR]

It is significant to develop low-cost and highly efficient electrocatalysts for the hydrogen evolution reaction (HER) via electrochemical water splitting. Herein, we constructed P-doped NiCo2S4 nanowire arrays on carbon fiber paper (NiCo2S4−xPx/CFP) as a HER electrocatalyst in both acidic and alkaline media. Benefitting from P doping into NiCo2S4, the as-prepared NiCo2S4−xPx/CFP exhibits low HER overpotentials of 80 and 132 mV in acidic and alkaline media at a cathodic current density of 10 mA cm−2, respectively, which are far superior to counterparts of NiCo2S4 nanowire arrays on the carbon fiber paper (NiCo2S4/CFP). Meanwhile, the NiCo2S4−xPx/CFP presents excellent HER stability of 20 hours in acidic and alkaline media. From the results of density functional theory calculations, P doping can not only optimize the hydrogen adsorption energetics on each kind of atomic site of catalysts, but also strengthen the H2O molecule binding ability on the catalyst surface for the alkaline HER and favor kinetics of hydrogen adsorption and H2 formation on the catalyst surface for the acidic HER, eventually improving overall HER performances. The investigation of the HER mechanism modulated by P doping in our work offers novel inspiration to develop highly efficient ternary metal sulfides for the HER. [ABSTRACT FROM AUTHOR]

Developing high-efficiency electrocatalysts for the hydrogen evolution reaction (HER) is of great importance. In this paper, dendrite-free Ni–Cu catalysts were synthesised via one-step pulse electrodeposition under a weak magnetic field (0.5 T). Regardless of the direction of the magnetic field, the ions were affected by the magnetohydrodynamic (MHD) effect, which greatly promoted the mass transfer and dispersion uniformity, and suppressed the uncontrollable agglomeration by electrodeposition. It was found that the nucleation mechanism changed from progressive nucleation under a 0 T magnetic field to instantaneous nucleation under a 0.5 T magnetic field. Large-scale (325 nm, 0 T) dendrite growth on the single-sided plane was successfully suppressed, and replaced by smaller (90 nm, 0.5 T) and uniformly distributed cluster growth around the carbon paper. In addition, the (111) plane was strengthened by the magnetic field. Electrochemical analysis showed that the Ni–Cu catalysts exposed more surface area and exhibited greatly enhanced catalytic activity, which only needed −57.3 mV to deliver the current density of 10 mA cm−2 with a small Tafel slope of 99.4 mV dec−1 in 1 M KOH. Overall, magneto-electrodeposition, especially under weak magnetic field conditions, provides great promise for the preparation of HER catalysts. [ABSTRACT FROM AUTHOR]

Bimetallic two-dimensional (2D) metal–organic framework (MOF) materials display excellent electrocatalytic performance due to the synergistic effect between metals and the advantage of the 2D structure. In this work, Cu was introduced into the 2D Co-MOF structure, and a 2D book-like CuCo-MOF structure was fixed on carbon fiber paper (CFP) for direct electrochemical glucose detection and oxygen evolution reaction (OER). The materials showed good electrocatalytic glucose detection performance with a sensitivity as high as 6.861 mA mM−1 cm−2 and a detection limit as low as 0.12 μM. For the OER, when the current density is 10 mA cm−2, the overpotential (η) is 340 mV, and good stability is maintained for about 10 h without current attenuation. This work not only exploits a new 2D MOF structure containing Cu, but also expands the potential of Cu-containing MOF materials in the electrocatalytic OER, making a contribution to the field of energy conversion and biomolecular sensing. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry is a publication that features articles and papers on various topics in chemistry. The current issue includes papers on lithium-sulfur batteries, graphene, and carbon nanotubes, among others. The journal is published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. The papers provide valuable insights and findings in their respective fields of research, covering topics such as compound synthesis, crystal structures, magnetic behavior, and the development of new materials for applications like photocatalysis and electrocatalysis. The journal also offers professional recognition and development opportunities for scientists. [Extracted from the article]

The New Journal of Chemistry, published by the Royal Society of Chemistry, features articles on a wide range of topics in chemistry. The current issue covers subjects such as nanosized metals, liquid catalyzed growth of graphene, and photocatalytic CO2 reduction. The journal aims to provide innovative and cutting-edge reports that have a strong chemical component and broad appeal. This document is a compilation of research papers from the journal, covering topics such as electrocatalysts, nanocomposites, halogenation reactions, supramolecular assembly, and more. The papers explore various applications, including agriculture and waste digestion. [Extracted from the article]

As one of the effective methods for hydrogen production, water electrolysis has been widely studied. However, the high overpotential challenge faced by the anode and the limitation of the electron transfer rate in this process significantly inhibit the efficiency of hydrogen production, which has become the main obstacle to overcome in the current research. The use of thermodynamically more favorable organic compounds to oxidize at the anode instead of traditional water oxidation (OER) is an effective strategy to optimize the process of electrolytic hydrogen production. In this paper, Ni3S2 catalysts co-doped with non-noble metals Li and Mn were prepared on nickel foam and used for the glycerol oxidation reaction (GOR) coupled with the hydrogen evolution reaction (HER). In alkaline solution, Li, Mn–Ni3S2@NF exhibits good GOR and HER performance. Specifically, overpotentials of 1.58 V vs. RHE and 0.54 V vs. RHE are required to reach a current density of 200 mA cm−2, respectively, and the catalytic performance of the material remains good after a long-term test. Li, Mn–Ni3S2@NF as a bifunctional catalytic material oxidizes glycerol to formate, and its faradaic efficiency (FE) is as high as 91%, and the volume of hydrogen production is close to the theoretical value. In addition, the replacement of the OER by the GOR can reduce the energy consumption by about 17.44%. [ABSTRACT FROM AUTHOR]

In this paper, a novel Pt/CoP/C photo-electro synergistic catalyst was successfully synthesized by a hydrothermal method combined with phosphorus doping treatment. The addition of Vulcan XC-72R is in favor of effectively preventing agglomeration of active catalytic sites, resulting in more uniform and smaller Pt and CoP nanoparticles. The as-obtained Pt/CoP/C shows excellent photo-electro catalytic performance for the HER with simulated solar light irradiation. The optimal hydrogen production is 5384.18 mmol h−1 g−1, which is obviously higher than that of the commercial catalyst (20 wt% Pt/C: 4608.52 mmol h−1 g−1). The research results show that introducing cobalt phosphide into the Pt catalyst can improve the electrocatalytic activity and stability for the HER; in particular, the existence of Co3O4 in Pt/CoP/C leads to an efficient photo-electro catalysis under irradiation, which significantly improves the catalytic activity of Pt. The results above provide a novel strategy for the rational design of cost-effective Pt-based composites towards a fast HER. [ABSTRACT FROM AUTHOR]

Designing a robust bifunctional water splitting catalyst at low cost is of great importance for water splitting. Herein, the in situ-generated MoS2/NiS2 nanosheet heterostructures by cobalt incorporation on carbon paper (Co–MoS2/NiS2/CP) are first obtained by applying a scalable chemical vapor vulcanization approach. Based on the synergistic effects of cobalt element doping and the construction of MoS2/NiS2 heterostructures, the much enhanced electrocatalytic performance for full water electrolysis is clearly revealed. In particular, the electronic structure of MoS2/NiS2 heterostructures was further effectively modified by cobalt incorporation along with the electron density of catalytic sites, which both promote the Volmer step to speed up alkaline hydrogen evolution reaction (HER) and optimize the oxygen-containing intermediate adsorption to enhance oxygen evolution reaction (OER). Consequently, Co–MoS2/NiS2/CP heterostructures presented low overpotentials (HER: η10 = 109 mV; OER: η10 = 323 mV) in the basic solution. Furthermore, Co–MoS2/NiS2/CP was designed as a two-electrode alkaline electrolytic configuration for full water electrolysis. This strategy experimentally illustrates the feasibility of designing a conventional electrocatalyst for water electrolysis via the cooperative effects of metal doping and heterostructured engineering. [ABSTRACT FROM AUTHOR]

Rational design and controllable synthesis of transition metal multi-anionic structures to cooperatively catalyze the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) remain a great challenge due to the requirements of high current density and long-term durability for water splitting. Herein, a self-supported sheet-on-sheet hierarchical interface was synthesized via a facile corrosion engineering strategy, where the Ni3S2 microsheet arrays were pre-grown on nickel foam and they provided abundant surface active sites to grow FeOOH nanosheets vertically. The obtained FeOOH/Ni3S2 heterostructure exhibited well-defined dimensions and intimate interface contact with oxygen and a sulfur anion structure, which can modulate the electronic structure of interfacial active sites. Hence, the optimized FeOOH/Ni3S2 required overpotentials of 345 mV and 269 mV to achieve a current density of 100 mA cm−2 for the HER and the OER, respectively. Moreover, it required a voltage of 1.855 V to achieve overall water splitting at a current density of 100 mA cm−2. The interfacial electronic interaction and multi-anionic hierarchical structure not only facilitate the electron transfer between the FeOOH/Ni3S2 surface and intermediate species but also accelerate the kinetic rate. This paper provides a new avenue to design multi-anionic hierarchical structures as cost-effective and highly stable electrocatalysts for practical overall water splitting. [ABSTRACT FROM AUTHOR]

The development of noble-metal-free electrocatalysts with high catalytic efficiency, low cost, and high durability in pH-universal media is encountering a bottleneck in practical applications. In this paper, Ni@MoN-700 coral hybrids were prepared using hydrogen evolution reaction (HER) catalysts, which were synthesized by a high-temperature reduction of NiMoO4 nanorods with urea. It was found that the annealing temperature seriously affects the surface morphology and chemical composition of the catalysts. Besides, structural reorganization occurred during the HER, which involved the joining of pyrrolic N, metal nitrogen, Mo3+, and Mo6+, governing the HER performance. Also, during the HER, Ni and Mo could synergistically improve the overall catalytic activity of the catalysts, via electronic interactions. These advantages endow Ni@MoN-700 with exceptional endurance and great HER activity, with a low overpotential of 30 mV and 76 mV at 10 mA cm−2 in alkaline and acidic media. These characteristics are similar to those of Pt under alkaline conditions. NiMoN catalysts show unusual activity and long-term stability, indicating a wide range of potential applications. [ABSTRACT FROM AUTHOR]

In this paper, NiCo2S4 was coated on the surface of WS2 of a 1T/2H mixed phase by a two-step hydrothermal method to form an in situ core–shell structure. The unique S-scheme heterojunction of the NiCo2S4@WS2 core–shell composite photocatalyst improved the easy recombination of carriers caused by the narrow band gap of NiCo2S4 and WS2, and improved the photocatalytic hydrogen production performance. The loading ratio of NiCo2S4@WS2, the addition of Eosin Y, and the pH value of TEOA were optimized. Under the optimal conditions, the hydrogen production rate reached 5.814 mmol g−1 h−1, which is about 8.55 times and 3.35 times the hydrogen evolution rates of NiCo2S4 and WS2, respectively. The composite catalyst exhibits excellent charge separation efficiency in photoelectrochemistry, PL and BET tests, carrier transport rate and large specific surface area that can provide more active sites, which are the main factors for the improvement of the hydrogen evolution performance. This paper demonstrates new design strategies to drive efficient photocatalytic hydrogen production by building in situ core–shell structures and optimizing the carrier transport paths, which will yield new insights. [ABSTRACT FROM AUTHOR]

In this paper, the structural characteristics and catalytic mechanism for hydrogen evolution of ammonia borane of non-metal (N, S) doped CoP catalysts were studied in detail by density functional theory (DFT) calculations. Specifically, we first investigated the structure of the cobalt phosphide catalyzed ammonia borane models. In addition, based on the most stable structures, the mechanism of the hydrogen evolution reaction of ammonia borane catalyzed by three catalysts was studied, and four feasible reaction paths for the hydrogen evolution reaction of ammonia borane catalyzed by three catalysts were discussed. By comparing the activation energies of the control steps of different reaction paths, the optimal reaction paths for the hydrogen evolution of ammonia borane catalyzed by three different catalysts were determined. The catalytic activities of the three catalysts for the hydrogen evolution of ammonia borane were compared. We found that the N-doped catalyst was beneficial to improve the catalytic activity of CoP for the catalytic hydrogen evolution of ammonia borane, while the catalytic activity of S-doped CoP for the catalytic hydrogen evolution of ammonia borane is relatively weak. These results reveal the relationship between the physical properties of CoP (and its non-metal-doped variants) and their catalytic activity. Finally, these findings can be used to explain the underlying mechanism reported in previous experimental studies from a microscopic perspective. [ABSTRACT FROM AUTHOR]

Cocatalysts are usually applied in the photocatalytic water splitting process to accelerate the kinetics of the hydrogen evolution reaction (HER). Specifically, the transition metal nitride (Mo2N) featuring a unique local surface plasmon resonance (LSPR) effect has exhibited great potential to function as a HER cocatalyst. However, the low metallicity of Mo2N hampers its ability to improve charge separation. To address this issue, transition metal atom doping (Co and Cu) engineering was used to modulate the electronic structure of Mo2N nanosheets to achieve a higher electrical conductivity and a lower hydrogen adsorption free energy (‖ΔGH*‖), thereby favoring the HER kinetics. Density functional theory (DFT) calculations and experimental results showed that Co-doping and Cu-doping mainly take place at Mo sites in the crystal structure of Mo2N to form stable structures of Co doped Mo2N (Co–Mo2N) and Cu doped Mo2N (Cu–Mo2N). Compared with pristine Mo2N, both Cu–Mo2N and Co–Mo2N demonstrated a much improved cocatalytic effect over g-C3N4 in promoting charge separation, accelerating HER kinetics and enhancing light absorption. The Co–Mo2N with the highest conductivity and lowest ‖ΔGH*‖ illustrated the best cocatalytic effect, and the H2 production performance (367.8 μmol g−1 h−1) of Co–Mo2N/g-C3N4 achieved was 10 and 5 times higher than those of Mo2N/g-C3N4 and Cu–Mo2N/g-C3N4. This paper provides significant guidance in the design and development of efficient cocatalysts for the HER application. [ABSTRACT FROM AUTHOR]

Increasing fossil fuel demands and growing concerns of global climate change have stimulated interest in the development of electrocatalysts to produce H2 as an alternative zero-emission fuel from the electrolysis of water via hydrogen evolution reaction (HER). Precious or non-precious catalysts are typically loaded on high surface area carbon materials, and these supports play a critical role in both thermodynamics and kinetics of the HER. In this paper, we evaluate the electrocatalytic activity of a molecular hydrogen evolving catalyst, diacetyl-bis(4-methyl)-3-thiosemicarbazone Ni(II) (Ni-ATSM), on three different carbon surfaces: glassy carbon, carbon paste and pencil graphite. The overpotential for each modified electrode was benchmarked at a current density of −10 mA cm−2. Carbon paste electrodes showed highest overpotentials (495 mV) compared to the other electrode surfaces. Polished pencil and glassy carbon modified electrodes performed similarly (η = 395 mV for GCE and η = 400 mV for pencil). Pencil electrodes etched in acetone overnight prior to Ni-ATSM deposition produced lowest overpotentials (η = 354 mV). Etching results in an increase in electroactive surface area and substantial decrease in the charge transfer resistance of the graphitic interface from 275 Ω to 50 Ω, verified using electrochemical impedance spectroscopy (EIS). Our studies demonstrate pencil graphite may serve as versatile, disposable, cost effective, and reproducible electrode surface for the evaluation of heterogeneous HER catalysts. Moreover, pencils can be easily cut with table saw to generate new surface for easy characterization of the surface such as electrochemistry, imaging and spectroscopy. [ABSTRACT FROM AUTHOR]

Cocatalyst loading is of critical importance in efficient photocatalytic water splitting over perovskite oxynitrides. Perovskite CaTaO2N was synthesized for enhancing photocatalytic hydrogen evolution via decoration of a Pt cocatalyst by impregnation–reduction and photodeposition methods. The Pt-loaded CaTaO2N photocatalyst evolves 6.4 μmol H2 per hour, with an apparent quantum yield as high as 0.67% at a wavelength of 420 nm. Decorating the cocatalyst with uniform dispersion and intimate contact onto the surface of narrow-bandgap perovskite oxynitrides is an efficient method to upgrade photocatalytic hydrogen evolution from water splitting. [ABSTRACT FROM AUTHOR]

The pursuit of developing highly potent and environmentally friendly photocatalysts for water dissociation is crucial for the advancement and storage of unlimited solar energy, although it remains a massive challenge. Herein, we conducted a screening process for the photocatalytic water splitting capabilities of a multitude of members from the extensive MA2N4 family. Using first-principles calculations, we found MoSi2N4, WSi2N4 and WGe2N4 structures with excellent potential for photocatalytic applications. To be specific, these members possess semiconductor characteristics, featuring suitable band gap structures and pronounced optical absorption capabilities in the UV-visible light spectrum. Our findings suggest that with nitrogen vacancies present on the surface, MoSi2N4, WSi2N4, and WGe2N4 all demonstrate near-zero Gibbs free energy in driving the hydrogen evolution reaction. Simultaneously, MoSi2N4, WSi2N4, and WGe2N4 can spontaneously catalyze the overall water splitting reaction under light illumination at pH values of 4, 12, and 8, respectively. This investigation provides fresh perspectives in terms of designing highly efficient photocatalysts. [ABSTRACT FROM AUTHOR]

Element doping and construction of heterojunction composites are the most common ways to enhance g-C3N4, which are very attractive in achieving high photocatalytic activity. In this study, 2D nanosheet structured BCN was obtained by doping B atoms with graphite carbon nitride. Subsequently, Ti MOFs were loaded on BCN to obtain a Z-scheme heterojunction composite TBCN through calcination. Under simulated sunlight, the photocatalytic hydrogen production rate of the TBCN heterostructure was 1242 μmol h−1 g−1, which was 2.2 times higher than that of BCN and 9.34 times higher than that of bulk graphite carbon nitride (GCN). Experimental results showed that the construction of a Z-scheme heterojunction composite (TBCN) could effectively adjust the material band gap position, expand the light absorption range, enhance electron transfer and inhibit electron–hole recombination, which are crucial for efficient photocatalysis. This study not only provides a strategy for constructing heterojunction composites in the field of g-C3N4 photocatalytic hydrogen evolution, but also deeply analyzes the electron migration direction and the reasons for enhancing carrier separation in the Z-type heterojunction scheme, thus providing potential guidance for future research. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs) containing S heteroatom are promising materials for applications in photocatalysis due to their donor–acceptor-type structures, which can improve the mobility of carriers in polymers. Herein, a series of composites (TTBT-COF@PEGx, x = 10, 20, and 30) were prepared based on CTF containing S heteroatom and polyethylene glycol (PEG) by a two-step reaction. The results show that the photocatalytic hydrogen evolution rate of TTBT-COF@PEG30 is 1.51 times that of pristine TTBT-COF. This significant improvement was attributed to PEG in the pores, which resulted in a stable layered structure, reuced distortion and deformation of the skeleton, and rapid separation and transportation of photogenerated electron holes. [ABSTRACT FROM AUTHOR]

The photocatalytic hydrogen evolution half-reaction (HER) is a promising technology for meeting future energy demands. An excellent photocarrier separation is essential for the HER. Here, a CdS/ZnS composite (CZS) with a dual photocarrier separation channel has been synthesized using the epitaxial growth method to achieve this aim. XRD and TEM show that pre-adsorption of S2− on the CdS surface facilitates the conversion of CdS into ZnS with a larger solubility product, implying a good carrier transport channel between CdS and ZnS. Based on XPS, PL, and photo-deposition experiments, a dual-channel photocarrier separation mechanism has been proposed, which is the source of the great photocarrier separation, and thus the hydrogen evolution rate of the CZS-2 sample (22.05 mmol g−1 h−1) becomes 18.5 and 73.5 times higher than those of CdS and ZnS. The apparent quantum yield (AQY) of CZS-2 at 420 nm is 4.68%. [ABSTRACT FROM AUTHOR]

Two new heteroleptic cobalt(III)dialkyldithiophosphate complex cations with a 1,2-bis(diphenylphosphino)ethane (dppe) ancillary ligand having formula [Co{S2P(OR)2}2(dppe)](B(C6H5)4) (R = –C2H5 (Co–Et); –CH(CH3)2 (Co–Pr)) have been synthesized and characterized spectroscopically as well as via single crystal X-ray diffraction analysis. The single crystal X-ray diffraction analyses reveal that the immediate geometries around Co(III) in both complexes are distorted octahedral, which are satisfied by four sulfur atoms of two dialkyldithiophosphate ligands and two phosphorus centers of the dppe ligand. These complex cations are neutralized by tetraphenyl borate B(C6H5)4 anions. The solid-state framework of both complexes are stabilized by C–H⋯π and C–H⋯C interactions. The nature of these interactions have been addressed with the help of Hirshfeld surface analysis, and percent contributions of pertinent interactions in the crystal structure of these complexes have been addressed using fingerprint plots. Both complexes have been used as heterogeneous electrocatalysts for the oxygen evolution reaction (OER). Results suggest that Co–Et is a better electrocatalyst for the OER, displaying an onset potential of 1.68 V and Tafel slope of 114 mV dec−1. Furthermore, in the homogeneous electrocatalysis of the hydrogen evolution reaction (HER) using trifluoroacetic acid, the overpotential for Co–Et and Co–Pr have been 1.05 V and 0.92 V, respectively, with turnover frequencies of 1518 s−1 and 287.5 s−1, respectively. Overall, heterogeneous OER and homogenous HER results suggest that Co–Et can be used as an efficient molecular electrocatalyst for oxygen/hydrogen evolution reactions. [ABSTRACT FROM AUTHOR]

Exploring efficient non-noble metal catalysts for the hydrogen evolution reaction (HER) will contribute to the development of clean and green energy technologies. Herein, we adopted a "waste utilization" strategy by using readily available and inexpensive coconut shell waste as a carbon source to synthesize carbon materials anchored with a Cu7Co alloy (Cu7Co/C) as a potential electrocatalyst for the hydrogen evolution reaction (HER). Utilizing a combination of hydrothermal and pyrolysis methods, the synthesized Cu7Co/C catalyst showcases superior HER electrocatalytic performance in alkaline solutions, with an overpotential of 134 mV at 10 mA cm−2 and a Tafel slope of 94 mV dec−1. The alloying of Cu and Co within Cu7Co/C markedly improves charge transfer capabilities, enhancing HER electrocatalysis. This research underscores the exceptional catalytic performance and stability of Cu7Co/C nanocomposites in alkaline media for the HER, attributed to a synergistic effect between the carbon derived from coconut shells and the bimetallic Cu7Co alloy. [ABSTRACT FROM AUTHOR]

Electrocatalysts for hydrogen production play a crucial role in advancing the green economy. However, the sluggish kinetics of the hydrogen evolution reaction (HER) limited its application. Therefore, efficient strategies with a tailored d-band center adjustment are highly desirable. In this study, we synthesized N, P-doped carbon matrix-confined Mo-doped FeP nanoparticles using a simple strategy to optimize the catalyst's d-band center. Mo-FeP@NPC presents an excellent HER performance of 63 mV (H2SO4) and 116 mV (KOH) at −10 mA cm−2 in acid and alkaline electrolytes, separately. Theoretical calculations confirm that the outstanding HER performance originates from the strong electronic coupling between atoms, thus upshifting the d-band center and increasing H intermediate adsorption on the active sites. Furthermore, the N, P-doped carbon matrix protects the Mo-doped FeP nanoparticles from aggregation, exposing more active sites during hydrogen production. This work provides new avenues for applying highly efficient metal phosphide catalysts for the HER. [ABSTRACT FROM AUTHOR]

FeCo2O4 is a potential OER catalyst, but its catalytic activity still needs to be further improved due to its poor electrical conductivity and low material utilization. In this paper, we construct oxygen-vacancy-rich two dimensional FeCo2O4 nanosheet materials using a liquid-phase reduction strategy. Benefiting from its large specific surface area, numerous surface catalytic sites, enhanced electrical conductivity, and modulated electronic structure, the catalyst exhibits an overpotential of only 270 mV at a current density of 10 mA cm−2, which is lower than that of the original FeCo2O4 nanosheets (420 mV). At the same time, the catalyst can run steadily for 20 hours without obvious decay. [ABSTRACT FROM AUTHOR]

Transition metal nitrides have good metallic conductivity and high pseudocapacitance, which have drawn extensive attention in the research of Zn-ion energy storage systems. In this paper, we present a novel fabrication of carbon cloth-supported TiN-coated carbon nanotube composites (TiN/CNTs@CC and TWC) via a CVD–ALD method using ethanol, TiCl4 and H2O as precursors. The prepared TWC composites can be used as self-supported electrodes with good flexibility and conductivity. Electrochemical performance tests show that the TiN/CNTs@CC electrode has a high specific capacitance of 363.5 F g−1 at 0.5 A g−1, good rate capability and excellent cycling stability with 92.9% capacity retention over 10 000 charge/discharge cycles. Impressively, the assembled zinc ion hybrid capacitor can achieve a high energy density of up to 81.8 W h kg−1 at a power density of 137.7 W kg−1. Even at a power density of 3013.7 W kg−1, a high energy density of 26.4 W h kg−1 is still achieved. This study provides a new insight into the application of nitride-derived carbon materials in zinc-ion hybrid capacitors. [ABSTRACT FROM AUTHOR]

Water electrolysis is one of the most promising approaches for producing hydrogen. However, the OER, kinetics are sluggish and necessitate highly efficient electrocatalysts to speed up the reaction. In this work, we used NiCo glycerate solid nanospheres as a precursor to construct Fe–Ni–Co trimetallic oxide nanospheres utilizing a solvothermal-annealing and stirring technique. The oxygen evolution reaction (OER) activity of the Fe–Ni–Co spheres was greatly enhanced after Fe doping. Among these samples, the FeNiCo-15 hierarchical yolk–shell spheres needed overpotentials of only 204 and 178 mV for the OER and HER, respectively, to drive a current density of 10 mA cm−2, and showed good electrochemical stability. Further, it also presented superior electrocatalytic activity in terms of full water splitting, which was comparable to the integrated performance of the Pt‖IrO2 couple. A cell voltage of only 1.61 V was required to attain a current density of 10 mA cm−2. This paper provides a promising method for developing efficient bifunctional electrocatalysts driving redox electrocatalysis. [ABSTRACT FROM AUTHOR]

Developing low-cost high-efficient electrocatalysts for alkaline hydrogen evolution reaction (HER) is of critical significance in hydrogen production via alkaline electrolyzers. Herein, we prepared CeO2/Co4N heterostructure for the catalyst in alkaline HER, which introduced a synergistic effect within the CeO2 and Co4N catalytic sites that facilitates the two consecutive steps in alkaline HER reaction. More importantly, plasma treatment was further applied to the material to tune the electronic structure of the catalytic sites by creating multiple anion vacancies. The introduced O vacancies accelerated the H2O cleaving process on CeO2, while the N vacancies in Co4N optimized the H adsorption strength on the Co sites. The catalytic activity of the catalyst improved significantly after plasma treatment. It only required an overpotential of 36 mV@10 mA cm−2 for the HER operated in 1 M KOH electrolyte and provided one of the best precious metal-free catalysts ever reported. [ABSTRACT FROM AUTHOR]

The efficient production of hydrogen through water electrolysis requires stable, high-performance and rather cost-effective electrocatalysts to promote the hydrogen evolution reaction (HER). Platinum (Pt) is known to be a benchmark electrocatalyst for the HER, but its high-cost is a major obstacle for large-scale applications. Therefore, reducing Pt loading on electrodes, with a minimal influence on the electrochemical performance is of significant importance. Here, we report on the effective utilization of Pt through a simple two-step magneto-electrodeposition synthesis method, leading to the formation of uniformly dispersed Pt/NiCu electrocatalysts with an excellent catalytic activity. Under optimum conditions, NiCu substrates are fabricated under a vertical static magnetic field of 0.5 T, followed by pulsed electrodeposition of Pt under the same magnetic field. The electrocatalyst (0.5 T NiCu + 0.5 T Pt) exhibits a high stability and superior HER activity, characterized by low overpotentials of 10.6, 54.6, and 87.8 mV obtained at current densities of 10, 100, and 200 mA cm−2, respectively, accompanied by a small Tafel slope of 13.4 mV dec−1 in alkaline media (1 M KOH). This work provides a new approach enabling the optimum utilization of Pt-based electrocatalysts employed for the HER. [ABSTRACT FROM AUTHOR]

The development of earth-abundant and high-efficiency electrocatalysts for overall water splitting is highly fascinating and still presents a challenge caused by the low activity for both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) at the same time. In this paper, active cobalt-doped pyrite nanospheres with a porous structure are fabricated for the first time as advanced catalysts for water splitting in an alkaline solution. With the incorporation of cobalt atoms, the electronic structure of pyrite is well-tuned, with high conductivity as well as more active sites being obtained, which finally results in a superior bifunctional water splitting performance. Only 1.60 V is required to reach the current density of 10 mA cm−2, which is smaller than that of other transition metal sulfides. [ABSTRACT FROM AUTHOR]

In contrast to irregular polycrystals, the orderly structure and the clear surface atomic termination layer of porous single crystals demonstrate unique physical and chemical properties, including excellent electrical conductivity, an extremely large specific surface area, a small grain boundary area and low interfacial resistance. This could provide sufficient well-defined active sites for improving the catalytic activity and stability. Here, we grow well-shaped porous single-crystalline vanadium nitride octahedra and irregular porous polycrystalline vanadium nitride from non-porous NH4V4O10 single-crystal precursors. These well-shaped porous single-crystalline materials show a superior hydrogen evolution reaction (HER) performance. When used as HER catalysts, the overpotential of the VN porous single crystal is only 74.67 mV at a current density of 10 mA cm−2. By contrast, the overpotential of the irregular VN porous polycrystal is 150.66 mV under the same experimental conditions, which demonstrates the unique nature of the porous single-crystalline octahedron material. In contrast to traditional irregular polycrystals, this paper inspires the construction of porous single-crystalline materials with a crystal structure of long-range order of in the micron range for significantly improving the electrocatalytic performance. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the electro-catalytic hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) of synthesized copper tungsten oxide@reduced graphene oxide (CuWO4@rGO) nanocomposites. The prepared CuWO4@rGO nanocomposites show bifunctional electro-chemical performances for the HER and OER via water splitting reactions in alkaline (0.5 M KOH) and acidic (0.5 M H2SO4) media. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) reveal superlative HER and OER performances of the CuWO4@rGO nanocomposites. The onset over-potentials of the CuWO4@rGO nanocomposites were found to be ∼270 and ∼330 mV for the OER in 0.5 M KOH and 0.5 M H2SO4, respectively, while the onset potentials were found to be ∼180 and ∼135 mV for the HER in 0.5 M KOH and 0.5 M H2SO4, respectively. The CuWO4@rGO nanocomposites also showed lower Tafel slopes of ∼110 and ∼315 mV dec−1 for the OER in 0.5 M KOH and 0.5 M H2SO4, respectively, while the Tafel slopes of the CuWO4@rGO nanocomposites were found to be ∼192 and ∼212 mV dec−1 for the HER in 0.5 M KOH and 0.5 M H2SO4, respectively. Hence, the small energy loss of low-cost electro-catalysts during electro-chemical water splitting reactions reveals comparable HER/OER performances with noble electro-catalysts. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) electrocatalysts are critical in minimizing energy loss during the anodic four-electron transfer process that is required for water oxidation. Improving and selecting optimal non-noble OER electrocatalysts are key strategies for elevating their overall performance and efficiency of energy storage and conversion. Eight NiCo2O4 electrocatalysts were synthesized using the hydrothermal method by changing the amount of urea as a nucleation agent and hydrothermal and calcination temperature to achieve an outstanding catalyst in terms of morphology and electrochemical activity. For examining the physicochemical properties of the electrocatalyst, analyses such as XRD, SEM, TEM, and EDS were conducted. Although XRD analysis revealed the formation of pure NiCo2O4 for all eight samples, SEM and TEM analysis unraveled the best electrocatalyst in terms of morphology to be NiCo-S3 (urea: 10 times higher, Thydrothermal: 120 °C, and TCalcination: 350 °C) and NiCo-S4 (urea: 10 times higher, Thydrothermal: 120 °C, and TCalcination: 400 °C) with a mum-flower-like shape and particle dimension between 20 and 45 nm. NiCo-S4 displayed robust electrochemical activity, primarily in the OER, with an overpotential of 327 mV at 10 mA cm−2 in 1.0 M aqueous KOH solution. The OER performance was enhanced as demonstrated by the exceptional durability of >24 hours and a Tafel slope of 79.7 mV dec−1. Electrochemical impedance spectroscopy (EIS) revealed a low resistance of 1.03 Ω and a double-layer capacitance of 2.43 mF cm−2, substantiating the outstanding OER performance of NiCo-S4. [ABSTRACT FROM AUTHOR]

Transition metal/nitrogen-doped carbon catalysts (M–N–C) show superior catalytic activity in electrocatalytic CO2 reduction due to their high atomic efficiency. In this work, a series of electrocatalysts with cobalt phthalocyanine (CoPc) highly dispersed on M–N–C were prepared. Compared to the pure M–N–C materials, all CoPc/M–N–C catalysts showed a significantly enhanced activity for CO2 reduction and suppressed hydrogen evolution reaction. Among these catalysts, CoPc/Fe–N–C exhibits an outstanding activity and selectivity for CO2 reduction with 99% faradaic efficiency for CO at a potential of −0.48 V vs. RHE. Obviously, such a composite strategy is considered as one of the effective methods to improve the selectivity of CO2 to CO. [ABSTRACT FROM AUTHOR]

Electro-catalytic water splitting is widely viewed as an efficient and viable strategy for green hydrogen production. Herein, we designed nanostructured nickel–cobalt alloy grown on the reduced graphene oxide-single walled carbon nanotube (rGO-SWCNT) thin film by means of electro-deposition, which was used to catalyze water splitting for hydrogen evolution reaction (HER) in an alkaline medium. It was found that the HER performance of nickel–cobalt alloys was determined by the Co/Ni ratio and better than their corresponding single components Co and Ni. Nickel–cobalt alloy with a Co/Ni ratio of 2 (CoNi21) exhibited the most notable HER efficiency with an overpotential of 83.5 mV and 291.8 mV vs. reversible hydrogen electrode at 10 mA cm−2 and 100 mA cm−2, respectively. Furthermore, the significantly lower Tafel slope (112.6 mV dec−1) of CoNi21 indicates that the HER kinetics of the nickel–cobalt alloy is accelerated due to the synergistic effect of Ni and Co. The charge-transfer resistance of CoNi21 is significantly low compared to any single component, validating the intensified interfacial charge transfer. Besides, CoNi21 has the highest active surface area of 147.1 mF cm−2 on the basis of the ECSA measurements, which can be beneficial for providing rich active sites. The CoNi21 catalyst offered excellent durability for HER in the alkaline medium. This work provides a combinatorial method integrating rich interfaces of Co–Ni alloy on highly conductive carbon substrate to design efficient and low-cost electrocatalysts for improving the HER performance. [ABSTRACT FROM AUTHOR]

It is highly urgent to develop efficient and stable non-precious metal electrocatalysts for water splitting. Here, we have successfully prepared a phytic acid (PA)-treated NiFe layered double hydroxide (LDH) catalyst. NiFe-LDH(PA) exhibits excellent catalytic activity towards the hydrogen evolution reaction (HER), the oxygen evolution reaction (OER), and overall water splitting (OWS) (η10 = 112 mV and η100 = 198 mV for the HER, η100 = 260 mV for the OER, and 1.69 V for OWS @ 100 mA cm−2) as well as remarkable stability during long-term testing (100 h for the HER, 90 h for the OER, and 100 h for OWS). The PA treatment accelerates the catalytic kinetics of NiFe-LDH(PA) and exposes more active sites, leading to enhanced charge transfer. This work demonstrates the significant potential of organic small molecules in modifying the performance of conventional catalysts. [ABSTRACT FROM AUTHOR]

As a dual-functional catalyst for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), Ru clusters have great potential, but there are certain difficulties regarding their stability on the substrate and the tunability of their electronic environment. Here, the S doped graphited biochar aerogel electrocatalyst was designed and synthesized using terrestrial lignin and algal polysaccharide as a carbon substrate. The Ru clusters were anchored on the S-doped carbon aerogel (P-Ru/SC) by carefully designing the Ru-S bond via a novel plasma assisted high temperature carbonization treatment. The optimized P-Ru/SC-2 catalyst exhibits excellent electrocatalytic performance for the HER and OER, achieving ultra-small overpotentials of 119.6 mV and 193.4 mV at 10 mA cm-2. The dual-electrode requires only 1.47 V to reach 10 mA cm-2. It is worth noting that a large number of S sites on graphited carbon can strongly interact with the Ru clusters, significantly improving the catalytic activity and stability for the HER and OER. [ABSTRACT FROM AUTHOR]

The design and construction of a duo-active electrocatalyst with effective performance and enhanced stability for overall water splitting have been in the spotlight to meet the demand for renewable energy. Herein, we report the fabrication of a stannatranone pillared metal-organic framework via a coprecipitation approach and further its decoration with gold nanoparticles (size D 10.86 nm) for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The Au-anchored Sn-Na MOF (Au NPs/Sn-Na MOF) exhibited a remarkable electric activity with low overpotential (Z) of 129 mV for the HER at a current density of 10 mA cm-2, and 650 mV for the OER at a current density of 20 mA cm-2. The slope values were found to be 62.3 mV dec-1 and 37.8 mV dec-1, respectively. The heightened OER and HER activities can be ascribed to its substantial electrochemically active surface area of 17.4 mF cm-2. The mechanistic studies revealed that Au NPs/Sn-Na MOF provides active surface sites for water adsorption and facilitates subsequent dissociation to form H2 and O2. Furthermore, the pillared structure of the MOF with stannatranone knots made the skeleton highly stable under basic conditions for its potential application in overall water splitting. [ABSTRACT FROM AUTHOR]

New heteroleptic dppe appended Co(III)-dithiocarbamate (dtc) complex cations with compositions [Co(S2CNEt2)2(dppe)](PF6) (Co-Et), [Co(S2CNPri2)2(dppe)](PF6) (Co-Pr) and [Co(S2CNBun2)2(dppe)](PF6) (Co-Bu) have been synthesized and characterized by microanalysis, spectroscopic methods and crystallographic analysis. The single crystal X-ray diffraction results indicated that in all three complexes, the coordination environment around Co(III) is distorted octahedral and Co(III) is coordinated to four sulfur centers of the two dtc ligands and the two phosphorus centers of the dppe ligand. These complexes serve as precursors to yield cobalt sulfide/cobalt phosphide nano-composites dCo-Et, dCo-Pr and dCo-Bu by solvothermal decomposition of Co-Et, Co-Pr and Co-Bu, respectively. The decomposed materials have been characterized by PXRD and SEM-EDAX and explored as potential electrocatalysts for both oxygen evolution and hydrogen evolution reactions in basic and acidic media, respectively. Catalytic activity is dependent on the precursor complex and best OER and HER activities are observed for dCo-Bu with an η10 of 230 mV and a Tafel slope of 192.11 mV dec−1 for the OER and an η10 of 470 mV and a Tafel slope of 126.21 mV dec−1 for the HER. [ABSTRACT FROM AUTHOR]

Seawater, a plentiful natural resource, is promising for hydrogen production compared to traditional electrocatalytic methods based on high-purity freshwater. This strategy shift addresses the challenge of limited freshwater resources and holds significant potential for desalination applications. Hence, identifying effective electrocatalysts for seawater electrolysis is imperative to alleviate freshwater resource scarcity and achieve large-scale hydrogen production. Herein, we report a catalyst comprising zero-dimensional (0D) nitrogen-doped carbon-coated FeNi3 nano-particles (FeNi3-NC) grown on NiFeOx nano-sheets for the hydrogen evolution reaction in alkaline seawater. The combination of FeNi3-NC and NiFeOx significantly enhances interfacial interactions, resulting in an elevated rate of electron transfer. The FeNi3-NC/NiFeOx catalyst requires a low overpotential of 65 mV to achieve a current density of 10 mA cm−2 in alkaline seawater. In addition, the electrolytic cell constructed using it and its precursor also exhibits excellent water-splitting characteristics and it exhibits remarkable long-term stability and corrosion resistance. This discovery presents an innovative approach for designing zero-dimensional/two-dimensional catalysts to facilitate large-scale hydrogen production through seawater electrolysis. [ABSTRACT FROM AUTHOR]

Tin disulfide (SnS2) is a highly promising anode material for sodium-ion batteries (SIBs) due to its substantial theoretical capacity stemming from alloying reactions and conversion mechanisms. Eliminating non-conductive binders and simplifying fabrication, the binder-free SnS2@carbon cloth (SnS2@CC) electrode is gaining attention. In this study, a one-step solvothermal synthesis was applied to fabricate binder-free SnS2@CC structures as SIB anodes. The electrochemical performance was enhanced by doping copper (Cu) into the SnS2 lattice. Solvothermal duration and Cu doping levels were systematically investigated to optimize the electrochemical properties of anodes. The Cu-doped SnS2@CC (Cu–SnS2@CC) electrodes exhibited superior electrical conductivity and sodium ion diffusion coefficients compared to those for the SnS2@CC electrodes. After 30 cycles, the Cu–SnS2@CC electrode prepared using a 15-h solvothermal process and 2% Cu doping achieved the highest capacity of 1092.8 mA h g−1 at 0.1 A g−1, while the SnS2@CC electrode yielded only 436.4 mA h g−1 under the same conditions. The optimized Cu–SnS2@CC electrode demonstrates excellent rate performance and cycling stability, with a capacity retention of 63% and Coulombic efficiency of 100% after 130 charge/discharge cycles. This research paves the way for high-performance, binder-free SnS2-based anodes in SIBs. [ABSTRACT FROM AUTHOR]

This study developed an efficient photocatalyst for hydrogen production, consisting of CdS nanorods and the CoTPPBr4 co-catalyst. The synthesized photocatalyst was characterized using a suite of techniques including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), photoluminescence (PL) spectroscopy, and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS). Additionally, transient photocurrent response and electrochemical impedance spectroscopy (EIS) were carried out to further probe the material's properties. Our findings demonstrate that the CoTPPBr4 co-catalyst significantly enhances the photocatalytic H2 evolution efficiency under visible light irradiation. Notably, among the tested photocatalysts, a 12.5% CoTPPBr4/CdS composite exhibited the most superior photocatalytic performance, achieving a hydrogen production rate of 41.3 mmol g−1 h−1, which is 4.1 times higher than that of pristine CdS. The introduction of CoTPPBr4 effectively facilitates charge transfer within CdS, enhances the separation efficiency of light-induced electron–hole pairs, and boosts the surface H2-evolution kinetics. This research not only introduces a promising photocatalyst for visible light-driven hydrogen production but also provides a way for the development of highly efficient and stable CdS-based hybrid semiconductor nanocomposites suitable for diverse photocatalytic applications. [ABSTRACT FROM AUTHOR]

The development of high-performance and highly stable electrocatalysts is crucial and challenging for the hydrogen evolution reaction (HER). MOFs complexed with SnS2 can form complexes with inserted structures, and their large specific surface area and numerous pores favor mass transfer, exposing the S active sites to more SnS2, improving the utilisation of the active sites and enhancing the catalytic activity for the HER. Structural collapse can be hindered to improve the stability of the HER composites. Herein, six different kinds of SnS2 were synthesized by a hydrothermal method under discrete conditions, and SI8-SnS2 was screened out to have optimal morphology and electrocatalytic performance. Two innovative SnS2@Ni-MOF and SnS2@HKUST-1 as efficient electrocatalysts were synthesized by a facile grinding method for hydrogen generation. SnS2@Ni-MOF and SnS2@HKUST-1 catalysts showed lower overpotentials of 117 mV and 142 mV at 10 mA cm−2 (η10) and smaller Tafel slopes (58 mV dec−1 and 93 mV dec−1) than six different kinds of SnS2, Ni-MOF and HKUST-1 in 0.5 M H2SO4. Meanwhile, the Cdl values for SnS2@Ni-MOF and SnS2@HKUST-1 were estimated to be 11.5 mF cm−2 and 8.0 mF cm−2, and the stabilities of SnS2, Ni-MOF, HKUST-1, SnS2@Ni-MOF, and SnS2@HKUST-1 were tested at a current density of 10 mA cm−2. The current densities of SnS2@Ni-MOF and SnS2@HKUST-1 were stable over 8 h compared to the pure samples, and SEM, XPS tests were run after the HER test, indicating that the materials have excellent electrocatalytic stability. The syntheses of SnS2@Ni-MOF and SnS2@HKUST-1 enhance their intrinsic catalytic activity, and the porous structure promotes mass transfer efficiency, thereby improving the HER performance, which will guide the development of new and promising electrocatalysts for HER. [ABSTRACT FROM AUTHOR]

The quest for efficient, cost-effective non-platinum catalysts for the hydrogen evolution reaction (HER) is critical to reduce energy losses in alkaline electrolyzers. NiCrO/MCu111 (M = Mn, Fe, Co and Ni) interface sites were designed to investigate the HER activity trend by the PAW-PBE method. The synergy effect between oxide and transition metals modulated the H2O adsorption activation and reduced the H2O dissociation energy barrier to around 0.12 eV. The BEP relationship between Ea and ΔEH* was established for H2O dissociation. The H2O adsorption and dissociation properties on NiMO/Cu111(M = Cr, Mn, Fe and Co) were investigated. NiCrO/Cu111 exhibited a better HER activity than NiMO/Cu111 (M = Mn, Fe and Co). The relationship between the energy barriers (Ea) and the reaction energies (ΔE) was elucidated through the BEP relationship, highlighting the influence of oxide's electronic effects on the activity. This work demonstrates an engineering strategy to design oxide/metal interface sites with a low-cost multimetallic composition and with tuned electronic structures to achieve excellent HER activity. [ABSTRACT FROM AUTHOR]

A new strategy for doping selenium and phosphide in hollow N-doped carbon nanobox (N-CNB)-based porous electrospun N-doped carbon nanofibers (CNFs) was developed. First, lightweight N-CNBs were produced. Then, a hybrid of N-CNBs and CNFs (CNBs/CNFs) was prepared using electrospinning/carbonization techniques. Eventually, P and Se atoms were doped into CNBs/CNFs using a thermal treatment approach to prepare Se/P@CNBs/CNFs. The electrocatalytic capability of the Se/P@CNBs/CNFs composite toward H2O2 oxidation was investigated for H2O2 sensing, which showed performance in a linear range from 200 μM to 1800 μM with a high sensitivity of 171 μA mM−1 cm−2 and a limit of detection (LOD) of 58 μM (S/N = 3). In addition, the ability of Se/P@CNBs/CNFs toward H2O2 sensing in human serum was studied. These results indicated the excellent electrocatalytic performance of the as-prepared Se/P@CNBs/CNFs, which could be related to the unique hollow CNBs/CNFs doped with P and Se elements with a mesoporous structure, the open channels for effective H2O2 diffusion, fast mass/electron transport, and synergistic effect between the P and Se and CNBs/CNFs. [ABSTRACT FROM AUTHOR]

Direct methanol fuel cells (DMFC) are a promising new energy source. However, the lack of high-performance and low-cost methanol oxidation electrocatalysts hinders their commercial application. Firstly, we successfully prepared NENU-5-derived molybdenum carbide material (Cu-MoC) via a co-precipitation and high-temperature carbonization method using a material composed of a copper-based metal–organic skeleton and a molybdenum-based carbide as the main body. Secondly, PtCu nano-alloy catalysts (Pt/Cu-MoC) were prepared using a unique, spontaneous single replacement reaction after metal–organic skeleton (MOF) carbonization. Through the synergistic effect between Pt and Cu and the strong interaction between Mo2C and PtCu, the electronic structure of the Pt is modified, the energy of the d-band center is reduced, electron exchange is accelerated, and catalytic activity is enhanced. Compared with a commercial Pt/C catalyst in alkaline environments, the Pt0.10/Cu-MoC catalyst has a better MOR catalytic activity (563.25 mA mgPt−1), which is 1.5 times higher than that of commercial Pt/C (376.67 mA mgPt−1). The Pt0.10/Cu-MoC catalyst has an onset potential for CO oxidation that is 16 mV lower than that of commercial Pt/C, indicating better resistance to CO poisoning. Exploring carbon materials derived from MOFs with excellent junction support and using them as carriers to prepare Pt-based catalysts is a practical and feasible approach. It provides a way to develop new Pt-based catalysts that perform efficient MOR. [ABSTRACT FROM AUTHOR]

Water electrolysis is considered the most promising technology for hydrogen production. In the present study, RCoFe (regulated cobalt ferricyanide) is synthesized via the co-precipitation method, which is characterized by physical and electrochemical properties. XRD confirmed the crystalline phase of RCoFe and the diffraction peaks are consistent with JCPDS#82-2284. FE-SEM examines the nanoplatelet morphology, which could help with the mass transfer of electrons during the electrochemical process. Here, RCoFe promotes the extensive activity for the OER (oxygen evolution reaction) with 270 mV/GC; 252 mV/NF at 10 mA cm−2. The lower Tafel value for RCoFe (78 mV dec−1/GC; 107 mV dec−1/NF) was derived from LSV when compared to IrO2 (98 mV dec−1/GC; 123 mV dec−1/NF) and stable for a long time with minimal loss of potential (130 h/GC-1.5%; 250 h/NF-1.8%) owing to citrus sap, which stabilized the electrocatalyst. After electrochemical treatment, the post-SEM morphology reveals that the nanoplatelets are completely bound together to enhance the OER process. [ABSTRACT FROM AUTHOR]