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Abstract We here report the fabrication of a core-shell WO 3 @ZnIn 2 S 4 heterostructure by an interfacial seeding growth strategy, which is implemented by direct growth of ZnIn 2 S 4 nanosheets on the surface of WO 3 nanorods with forming a strong electronic interaction between two semiconductors that are beneficial for promoting the interfacial charge transfer. Systematic studies demonstrate that the WO 3 @ZnIn 2 S 4 nanohybrids hold superior performance for photocatalytic hydrogen generation under visible light irradiation with a production rate of 3900 μmol g−1 h−1. This work provides an effective approach to construct the direct Z-scheme photocatalytic systems for efficient photocatalytic hydrogen evolution, which would be significant for the design of more direct Z-scheme system for various photocatalytic applications. [ABSTRACT FROM AUTHOR]

Exploring low-cost, highly efficient, and sustainable non-precious electrocatalysts for electrolytic H 2 generation is driving research for the sustainable green urban development. Herein, we present a simple synthetic approach, through a two-step process, to prepare the bifunctional electrode of Co 3 O 4 –C@FeMoP hybrid micro rods/nanosheets anchored on nickel foam (NF), in which the Co 3 O 4 –C microrods grown on NF surface are decorated by FeMoP nanosheet layers, which is directly grown through a simple hydrothermal followed by post-phosphorization processes. The obtained hybrid hierarchical Co 3 O 4 –C@FeMoP/NF shows a significant enhancement in the electrocatalytic activities of oxygen/hydrogen evolution reactions (OER/HER) in comparison to the individual Co 3 O 4 –C and FeMoP nanostructures, thanks to more heterointerface active sites provided by FeMoP nanostructures with three-dimensional (3-D) layered architectures. The Co 3 O 4 –C@FeMoP/NF catalyst exhibits a relatively small overpotential of 200 mV vs. RHE for OER to achieve 20 mA/cm2 and 123 mV vs RHE at 10 mA/cm2 for HER along with excellent durability in alkaline electrolytes. We demonstrate the bifunctional electrocatalytic electrode as the electrolyzer for the generation of H 2 via water splitting at small applied voltage of 1.61 V to achieve 10 mA/cm2 and good stability for 24-h continuous running. • Synthesis of high-activity catalyst material Co 3 O 4 –C@FeMoP/NF. • Decent electrocatalytic activity toward OER and HER in alkali. • Alkaline water electrolysis system with bifunctional electrocatalyst electrode. [ABSTRACT FROM AUTHOR]

It is vital to develop a high activity, stability and inexpensive hydrogen evolution reaction (HER) catalyst for electrochemical hydrogen evolution. A high-temperature reaction approach that is Co nanocrystals on carbon support (XC-72R) and selenylation to synthetize CoSe 2 /C nanocrystals is used, and the effect of temperature on CoSe 2 /C nanocrystals is studied. The morphology and catalytic properties of CoSe 2 /C nanocrystals annealed at different temperatures are compared in 0.5 M H 2 SO 4. The results indicated the coralline-like CoSe 2 /C-650 nanocrystals have a high performance for HER with Tafel slopes of 45.73 mV·dec−1 and onset potential of −196 mV vs. RHE. The stability maintained for at least 40 h and the Faraday Efficiency (FE) of H 2 is nearly 98%. The outstanding HER performance of CoSe 2 /C-650 is due to its characteristic cora-like frame CoSe 2 nanocrystals embedded into supernal conductive XC-72R, which not only offer affluent active reaction sites, but also boost the capacity of charge transportation in HER process. A reliable strategy is developed to fabricate coralline-like CoSe 2 nanocrystals on carbon support (XC-72R); the effect of temperature on controlling CoSe 2 nanocrystals is studied. The coral-like CoSe 2 /C-650 shows high catalytic activity and stability, superior to that the obtained CoSe 2 at other temperature, the onset potential for HER of −196 mV vs. RHE and Tafel slopes of 45.73 mV·dec−1. The electrode also has excellent durability, catalytic activity being maintained for over 40 h and the FE was calculated of H 2 is nearly 98%. The unique cora-like architecture constructed by CoSe 2 nanocrystals embedded into highly conductive XC-72R, which can not only offer rich active reaction sites, but also boost the ability of charge transportation in HER process. Image 1 • A CoSe 2 nanocrystals embedded into carbon support show a coralline-like structure. • The effect of temperature on controlling CoSe 2 nanocrystals. • The CoSe 2 /C-650 with a Tafel slopes of 45.73 mV•dec−1. [ABSTRACT FROM AUTHOR]

The rational design of cost-effective and high-activity electrocatalyst for hydrogen evolution reaction (HER) is a crucial field of research for achieving the best way to promote “green energy”. Here, we develop a simple route to prepare nanohybrids of three-dimensional graphene loading MoO 2 Mo 2 C nanoparticles (MoO 2 Mo 2 C/G), which were characterized using X-ray diffractometer (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), demonstrating the MoO 2 Mo 2 C/G has unique features with high conductivity, robust structure, and high surface area. The as-developed MoO 2 Mo 2 C/G nanohybrid shows great potential to replace Pt-based electrocatalyst for hydrogen evolution reaction (HER) due to its cheapness, high catalytic activity and considerable stability. [ABSTRACT FROM AUTHOR]