▎ 摘　　要

Electrocatalysts have been used to split water into hydrogen and oxygen for their advantages in clean energy technologies. To reduce cost and enhance stability of electrocatalysts, intensive works have been done in recent decades. Although research on noble-metal free electrocatalysts has achieved great progress, their full water splitting performance is still incomparable to that of noble metal based catalysts. For this reason, reducing content of noble metal in catalysts is a more practical way. In this work, we report our recent progress on developing bifunctional electrocatalyst based on nitrogen-doped graphene chainmail wrapped IrCo alloy particles on nitrogen-doped graphene (NG@IrCo/NG). Benefited from strong interaction among iridium, cobalt and nitrogen-doped graphene, impressively high electrocatalytic activity of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in both acid and alkaline solutions, which are comparable to commercially used Pt/C and IrO2 electrocatalysts respectively, is found. Catalyst with the structure of nitrogen doped chainmail wrapping on metal core is found to have highly stable full water splitting performance.