Controlled synthesis of high-density metal atom interface defects for acid water oxidation

Controlled selective growth of an interface with high-density active sites is the key to constructing efficient and long-term stable proton exchange membrane water electrolysis, which can effectively promote an acidic oxygen evolution reaction. Herein, a 2D all-carbon graphdiyne (GDY) is used as an ideal support to grow a new generated interface of RuO _x /GDY and finally to achieve the directed and controlled production of high-density Ru atom defects. The metal atom defect-rich interface not only afforded high intrinsic activity by facilitating the adsorption/desorption ability of reaction intermediates, but also enhanced structural stability by forming interfacial chemical bonds. RuO _x /GDY shows a small overpotential of 157 mV at 10 mA cm^-2 and 100 h of stability in acidic electrolyte. The proton exchange membrane water electrolyser when using RuO _x /GDY as the anodic catalyst only requires 1.47 V to achieve 1000 mA cm^-2 and the estimated cost of hydrogen production is US $0.78 kg^-1 H₂.