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The sluggish anodic oxygen evolution reaction (OER) greatly hinders the working efficiency of electrochemical water splitting to produce hydrogen, and it is therefore important to explore high-performance and cost-effective OER catalysts. In this communication, we report the synthesis of cobalt boride incorporated within porous carbon using a metal–organic framework (MOF) as a precursor. The high catalytic activity of Co–B and the high conductivity of carbon both contribute to the OER catalytic activity of Co–B/C. When used as an OER catalyst, this material shows high catalytic activity, delivering a current density of 10 mA cm − 2 at a low overpotential of 320 mV, as well as outstanding long-term electrochemical durability. This finding is of fundamental and practical importance as it not only extends the application of MOFs, but also introduces a new method for synthesizing highly efficient OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Designing efficient oxygen evolution reaction (OER) electrocatalysts is crucial for practical applications in water splitting and metal-air battery devices. Special structures of materials often bring in unprecedented catalytic activity. Herein, we first report the synthesis of CoMoO 4 nanotube by using MoO 3 @ZIF-67 nanorod. The CoMoO 4 nanotube shows high OER activity with a low overpotential of 315 mV delivering a current density of 10 mA cm−2. The electro-catalytic activity surpasses that of many Co and Mo-based catalysts. Furthermore, the strategy presented here is facile, and can be extended to the synthesis of other Mo-based nanotube materials for energy storage and conversion. Unlabelled Image • CoMoO 4 nanotube was prepared by using MOF composite as precursor for the first time. • The CoMoO 4 shows high a specific surface area of 157 m2 g−1. • The CoMoO 4 shows high OER activity of 10 mA cm−2 at an overpotential of 315 mV. • The CoMoO 4 also shows outstanding long-term electrochemical durability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow CoVO x /Ag heterojunction was synthesized for OER. • The interaction of CoVO x and Ag nanoparticles regulated the electronic structure. • The extrinsic catalytic activity of CoVO x /Ag is enhanced due to the hollow structure. • The OER overpotential for CoVO x /Ag-5 at 10 mA cm−2 is only 247 mV. • The catalyst can enable full water splitting with 100% Faraday efficiency. Developing high-active and inexpensive electrocatalysts for oxygen evolution reaction (OER) is very important in the field of water splitting. The catalytic performance of electrocatalysts can be significantly improved by optimizing the electronic structure and designing suitable nanostructure. In this work, we represent the synthesis of hollow CoVO x /Ag-5 for OER. Due to the interaction of CoVO x and Ag nanoparticles, the electronic structure is optimized to improve the intrinsic catalytic activity. Additionally, the extrinsic catalytic activity of CoVO x /Ag is enhanced by the abundant active sites from the hollow structure. As a result, the CoVO x /Ag-5 demonstrates significantly enhanced OER catalytic activity with a low overpotential of 247 mV at 10 mA cm−2. In addition, it also exhibits excellent durability, without obvious attenuation in performance after continuous operation for 60 h. Furthermore, the catalyst can enable full water splitting with appropriate 100 % Faraday efficiency, demonstrating its practical application. [ABSTRACT FROM AUTHOR]

A novel CoMoO 4 -RuO 2 heterogeneous catalyst with flower-liked morphology was developed as a highly efficient bifunctional oxygen electrocatalyst for Zn-air battery. [Display omitted] Constructing heterogeneous catalysts can significantly boost the electrocatalytic activity due to the improved intrinsic catalytic activity induced by tailored electronic structure and optimized chemisorption to the reaction intermediates. RuO 2 based electrocatalysts are especially attractive due to the high catalytic activity of RuO 2. To reduce the usage of noble metal and improve the catalytic activity of catalyst, CoMoO 4 -RuO 2 micro-flower was synthesized using a facile hydrothermal-calcination method in this work. CoMoO 4 -RuO 2 exhibits a low overpotential of 177 mV at 10 mA cm−2 for oxygen evolution reaction (OER) and a high half-wave potential of 0.858 V for oxygen reduction reaction (ORR). Moreover, the Zn-air battery assembled using CoMoO 4 -RuO 2 exhibit shows a high maximum discharge power density of 149 mW cm−2 and a large open circuit voltage of 1.38 V. The good performance can be attributed to the incorporation of RuO 2 , which not only induces extra catalytic active sites, but also forms heterojunction with CoMoO 4 to optimize the electronic structure of CoMoO 4 -RuO 2 , thereby achieving a better equilibrium of absorption and desorption of intermediates. The work provides insights into designing RuO 2 based electrocatalysts for advanced electrocatalysis. [ABSTRACT FROM AUTHOR]

Developing high‐efficiency bifunctional electrocatalysts for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) to realize low‐cost water splitting is the premise for large‐scale production of hydrogen. The catalytic activity of an electrocatalysts greatly depends on its composition and structure. In this work, we report the preparation of hollow CoS2/MoS2 heterostructure using ZIF‐67 as the precursor. The ratio of Co and Mo are optimized to maximize the synergy of CoS2 and MoS2, due to their specific catalytic activity for OER and HER. The optimized CoS2/MoS2 exhibits good bifunctional catalytic activity in view of its low overpotentials for HER (170 mV) and OER (270 mV), as well as small cell voltage of 1.66 V for overall water splitting. This work provides a facile strategy to controllable fabrication of efficient bifunctional electrocatalysts for renewable energy applications. [ABSTRACT FROM AUTHOR]

CoS 2 @MoS 2 @NiS 2 nano polyhedron with double-shelled structure was demonstrated to have multiple catalytic activity for HER, OER and ORR, which could serve as highly efficient catalysts for both rechargeable Zn-air batteries and overall water spitting. [Display omitted] • Double shelled hollow CoS 2 @MoS 2 @NiS 2 polyhedron was synthesized using a self-template method. • The CoS 2 @MoS 2 @NiS 2 exhibits multiple catalytic activity for HER, OER and ORR. • The CoS 2 @MoS 2 @NiS 2 exhibits a low HER overpotential of 156 mV at 10 mA cm−2. • The OER and ORR performance was demonstrated by rechargeable Zn-air battery. • The Zn-air battery can effectively drive water splitting device catalyzed by CoS 2 @MoS 2 @NiS 2. Electrocatalysts play important role in various energy conversion and storage devices. The catalytic performance of electrocatalysts can be enhanced through the increasement of intrinsic catalytic activity by optimizing electronic structure and the improvement of exposed active sites by designing proper nanostructures. In this work, CoS 2 @MoS 2 @NiS 2 nano polyhedron with double-shelled structure was prepared using metal organic framework as a precursor. Due to the rational integration of multifunctional active center, the strong electronic interaction of the various component, the high electrochemical surface area and shortened mass transport induced by the special structure, CoS 2 @MoS 2 @NiS 2 exhibits high catalytic activity for hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). Specifically, low overpotentials of 156 and 200 mV was achieved to deliver a current density of 10 mA cm−2 for HER and OER, and a high half-wave potential of 0.80 V was observed for ORR. More importantly, the Zn-air battery assembled by CoS 2 @MoS 2 @NiS 2 exhibits a high-power density of 80.28 mW cm−2 and could effectively drive overall water splitting. This work provides a new platform for designing multifunctional catalysts with high activity for energy conversion and storage. [ABSTRACT FROM AUTHOR]

Summary: The electrocatalytic CO2 reduction reaction (CO2RR) can convert greenhouse gases into high value‐added carbon‐based fuels and chemicals, providing a sustainable way to solve the energy and environmental crisis. Currently, AuCu bimetallic alloys are attracting attention because of their potential to customize the catalytic activity. In this work, the stability of Au and AuCu bimetallic clusters are systematically studied by first principles calculation. On this basis, the AuCu cluster catalyst is simulated using the density functional theory (DFT) to detect its catalytic activity for the reduction of CO2 to CH3OH. The calculation results show that the AuCu clusters with symmetry have the best stability. Moreover, the doping of Cu atoms in the Au6 cluster can reduce the reaction barrier to a certain extent, thereby accelerating the reaction. Among them, Au1Cu5 and Au2Cu4 cluster catalysts have the most obvious catalytic effects. In the last step, the energy can be reduced by about 2.688 and 5.404 kcal·mol−1, respectively, which can realize the synergistic catalytic effect of Au and Cu on CO2RR. This work can be helpful for the design and preparation of high‐efficiency bimetallic cluster catalysts for CO2RR to CH3OH. [ABSTRACT FROM AUTHOR]

Transition-metal chalcogenides especially MoS 2 are promising candidates as highly efficient electrocatalyst for hydrogen evolution reaction (HER). Nevertheless, the low conductivity and inert basal planes of MoS 2 limit its performance. In addition, the oxygen evolution reaction (OER) catalytic activity of MoS 2 is low. In this work, we report the synthesis of self-supported 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 nanoarrays for overall water splitting. 1 T-MoS 2 can enhance electron transfer during the reaction process. Meanwhile, abundant interfaces and defects exist in the heterogeneous catalysts, which can bring more active sites and result in strong interaction among the different components. As a result, the 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 nanoarray exhibits low overpotentials of 50 and 240 mV is achieved at 10 mA cm−2 for HER and OER with very high stability. In addition, it can catalyze overall water splitting with a low cell voltage of 1.55 V and 100% Faradic efficiency, demonstrating its practical applications. The present work offers a new route for developing 1 T-MoS 2 based hybrid electrocatalysts with desirable surface and interface structure for energy storage and conversion. [Display omitted] • Self-supported 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 nanoarrays was developed for overall water splitting. • The abundant interfaces and defects in 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 benefit its catalytic activity. • 1 T-MoS 2 can accelerate electron transfer during the catalytic process. • 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 exhibits low HER and OER overpotentials of 50 and 240 mV. • 1 T-MoS 2 /Co 3 S 4 /Ni 3 S 2 can drive full water splitting at 1.55 V with 100% Faradic efficiency. [ABSTRACT FROM AUTHOR]

• Co-Co 6 Mo 6 C 2 @NC nano polyhedron was synthesized using ZIF-67 as a precursor. • The Co 6 Mo 6 C 2 can significantly improve the OER catalytic activity of the catalyst. • The Co-Co 6 Mo 6 C 2 @NC-5 exhibits a low OER overpotential of 270 mV at 10 mA cm−2. • The Co-Co 6 Mo 6 C 2 @NC-5 exhibits a high ORR half-wave potential of 0.80 V. • The Co-Co 6 Mo 6 C 2 @NC can be used as a bifunctional electrocatalyst for Zn-air battery. A high effective bifunctional electrocatalyst was developed for rechargeable Zn-air batteries by rational integrating high active Co sites for ORR and Co 6 Mo 6 C 2 specie for OER. [Display omitted] To facilitate the development of rechargeable metal-air batteries, the exploration of high effective bifunctional electrocatalysts is essential. In this work, we report a facile strategy to synthesize N doped carbon (NC) encapsulated Co-Co 6 Mo 6 C 2 (Co-Co 6 Mo 6 C 2 @NC) nano polyhedron using ZIF-67 as a precursor and investigated its catalytic performance for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). The introduction of Co 6 Mo 6 C 2 into Co@NC can significantly improve the OER catalytic activity of the catalyst, while the high ORR catalytic activity of the catalyst is maintained. Specifically, Co-Co 6 Mo 6 C 2 @NC-5 shows a decent half-wave potential of 0.80 V for ORR, and a very low overpotential of 270 mV at 10 mA cm−2 for OER, demonstrating its bifunctional activity. The rechargeable Zn-air battery assembled using Co-Co 6 Mo 6 C 2 @NC-5 exhibits a maximum power density of 90.75 mW cm−2 and a high specific capacity of 768 mA h g−1, as well as good durability of 50 h without attenuation in performance, highlighting its practical application. [ABSTRACT FROM AUTHOR]

• Mechanism of NRR occurred on Ru/graphene catalysts were studied by DFT. • The effects of Ru atom numbers and Ru atom distribution on Ru/Gr were studied. • Provide guidance for the design and preparation of NRR catalysts. As a more common catalyst material in nitrogen reduction reactions (NRR), Ru has high activity and considerable catalytic performance, but it is expensive with scarce reserves. These factors limit the development of Ru in NRR, how to reduce costs and increase the utilization of precious metals is a problem facing the development of Ru-based catalysts. Graphene is considered as a promising carrier material, which can increase the specific surface area and dispersibility of the catalyst, thereby improving the utilization rate of materials. Therefore we combined these two materials and studied the mechanism of NRR occurred on Ru/graphene (Gr) catalysts by density functional theory (DFT) method. The effects of different numbers of Ru atoms and Ru atom distribution on the catalytic activity of Ru/Gr catalyst were calculated. A series of data such as the adsorption free energy and reaction path were obtained. The final results show that the double Ru supported graphite nitrogen doped Gr with single adsorption process and the three Ru supported pyrrole nitrogen doped Gr with double adsorption process have the best NRR activity. Compared with catalyst-free process, the presence of the catalyst effectively reduces the reaction energy barrier and improves the reaction activity. The research results provide guidance for the design and preparation of high-performance NRR catalysts to a certain extent. [ABSTRACT FROM AUTHOR]