▎ 摘　　要

The development of transition metal electrocatalysts to replace precious metal electrocatalysts is essential for the development of sustainable water splitting technology for the mass production of clean hydrogen. FeCoNiS/NVG (N-doped vertically oriented graphene) is fabricated via single-step electrodeposition. Benefiting from the vertical structure of FeCoNiS/NVG and intrinsic catalytic activity of FeCoNiS, FeCoNiS/NVG displays excellent catalytic activities toward the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), with overpotentials of 126 and 347 mV at 10 mA cm(-2), respectively. The overpotentials of FeCoNiS/NVG are similar to those of commercial Pt/C (100 mV) and IrO2 (329 mV). The Faraday efficiency of FeCoNiS/NVG for overall water splitting is about 95%. FeCoNiS/NVG also exhibits long-term stability for HER and OER. This work demonstrates the great potential of iron-group metal sulfides for overall water splitting. (C) 2021 The Electrochemical Society ("ECS"). Published on behalf of ECS by IOP Publishing Limited.