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-FeNi3 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, η20 = 240.0 mV, η1000 = 330.0 mV) and hydrogen evolution reaction (HER, η10 = 31.1 mV, η1000 = 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 FeNi3 can promote the intrinsic activity of catalyst. Therefore, this work proposes an industrially promising catalyst for water splitting.