▎ 摘　　要

The design and synthesis of bifunctional electrocatalysts with high catalytic activity and low cost are the key factors to efficient overall water splitting (OWS). In this work, CoNiO2 (CNO) microspheres with multiple microstructures are loaded on the N and S co-doped reduced graphene oxide (NSG) via an easy synthesis process to improve the conductivity and electrochemistry activity of CNO@NSG. The overpotentials of CNO@NSG are 109.6 mV and 287.4 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) with the load mass of 0.1 mg/cm2 and the potential in OWS of CNO@NSG at the 10 mA/cm2 is 1.67 V. These results suggest that cobalt-based oxides with carbon-carrier bifunctional electrocatalyst provide a new practical method for OWS.