Industrially promising IrNi-FeNi3 hybrid nanosheets for overall water splitting catalysis at large current density

Preparing efficient and stable catalysts is one of the most urgent problems for water splitting. Herein, IrNi-FeNi 3 hybrid self-supported on nickel foam with unique nanosheets and 1.218 wt.% Ir-loading is synthesized via hydrothermal method. In 1.0 M KOH, ultralow overpotentials for oxygen evolution reaction (OER, η 20 = 240.0 mV, η 1000 = 330.0 mV) and hydrogen evolution reaction (HER, η 10 = 31.1 mV, η 1000 = 288.8 mV) are needed. Only 1.47 V is required for overall water splitting to arrive at 10 mA cm −2 , indicating superior activity. For overall water splitting, it also demonstrates good stability with negligible declines after testing for 100 h at 500 mA cm −2 in 6.0 M KOH at 60 ℃, which is close to the practical application. The unique self-supported nanosheets structure on nickel foam can expose more active sites and the hybridization of IrNi with FeNi 3 can promote the intrinsic activity of catalyst. Therefore, this work proposes an industrially promising catalyst for water splitting.