Electrodeposition-derived defect-rich heterogeneous trimetallic sulfide/hydroxide nanotubes/nanobelts for efficient electrocatalytic oxygen production

Abstract Developing heterogeneous polymetallic sulfide/hydroxide nanotubes or nanobelts as highly efficient and noble-free electrocatalysts for oxygen evolution reaction (OER) with sluggish kinetics is rarely reported. Herein, defect-rich heterogeneous crystalline (Ni, Fe, Co)S2/amorphous NiFeCo(OH)y nanotubes/nanobelts (nNFCS NTs/NBs) are fabricated mainly by a facile cyclic voltammetry electrodeposition. By enriching exposing active sites and optimizing coordination environment via the construction of crystalline sulfide/amorphous hydroxide heterostructures, incorporation of Fe, Co, Ni, rich surface defects, and one-dimensional NTs/NBs structure, the nNFCS catalyst presents a fascinating OER electrocatalytic activity. Ultralow overpotentials of 193 and 225 mV at 10 and 150 mA cm−2, respectively, are achieved with a small Tafel slop of 36.9 mV dec−1, which excels most reported sulfide, hydroxide catalysts and IrO2. This work offers a significant guidance for designing advanced earth-abundant OER catalysts by incorporating several strategies of enriching surface defects and elevating catalytic activity properly.