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Development of efficient catalyst with low-cost, earth-abundant metals for sustainable hydrogen generation is still an intriguing challenge. Doping of cation or anion is regarded as an effective approach for ingenious modulation of chemical composition related to the electrocatalysts for improving their activity. Herein, a ternary Ni(S 0.49 Se 0.51 ) 2 porous flakes array on carbon fiber cloth (CFC) via simultaneous sulfuration and selenylation of Ni(OH) 2 flakes. Owing to the synergistic effect between Ni, S and Se atoms, high surface area, abundant active site and good conductivity of the Ni(S 0.49 Se 0.51 ) 2 /CFC, the as-synthesized catalyst requires lower overpotential (113 mV) than pure NiS 2 /CFC and NiSe 2 /CFC to drive 10 mA cm −2 for hydrogen evolution reaction (HER) in 1.0 M KOH with good sustainability. [ABSTRACT FROM AUTHOR]

Abstract The development of bifunctional catalysts that can be applied to both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is widely regarded as a key factor in the production of sustainable hydrogen fuel by electrochemical water splitting. In this work, we present a high-performance electrocatalyst based on nickel-cobalt metal-organic frameworks for overall water splitting. The as-obtained catalyst shows low overpotential to reaches the current density of 10 mA cm−2 with 249 mV for OER and 143 mV for HER in alkaline media, respectively. More importantly, when the electrolyzer was assembled with the as-prepared catalyst as anode and cathode simultaneously, it demonstrates excellent activity just applies a potential of 1.68 V to achieve 10 mA cm−2 current density for overall water splitting. Graphical abstract Image 1 Highlights • NiCoSe/C was prepared by direct selenylation of Ni/Co metal-organic framework. • The NiCoSe/C catalyst shows high performance for both OER and HER. • The NiCoSe/C catalyst shows efficient overall water splitting property. [ABSTRACT FROM AUTHOR]

Abstract Facile fabrication of high-performance catalyst based on low-cost metals for sustainable hydrogen evolution is still a matter of cardinal significance. However, synthetic approaches for electrocatalyst are usually complicated and the yields are often low. Herein, we report a one-step simple method for the large-scale synthesis of Co/Ni-MoO 2 composite as efficient and stable hydrogen evolution reaction (HER) electrocatalyst to drive 10 mA cm−2 current density with a low overpotential of 103 mV in basic media. Co-MoO 2 and Ni-MoO 2 were also prepared using this method with overpotential of 137 and 130 mV, respectively, to gain the same current density. These results indicate that this facile synthesis approach is of great practical importance as it can be easily used for large-scale preparation of electrocatalysts in industry. Highlights • A facile one-step method for synthesis of Co/Ni-MoO 2 composite was developed. • Co/Ni-MoO 2 supplies two kinds of active sites including Co/Ni specie and MoO 2 specie. • The catalyst exhibits excellent catalytic performance for HER. [ABSTRACT FROM AUTHOR]