Heterostructure design of CoMoS2/NiSe2-induced electric field engineering toward efficient water electrolysis

Abstract

Rational creation of efficient, stable, and economical bifunctional electrocatalysts is highly desired for water splitting.CoMoS2/NiSe2 heterostructure electrocatalyst supported on nickel foam (NF) was successfully synthesized using a hydrothermal method. The distinctive chrysanthemum-like hierarchical architecture of CoMoS2/NiSe2 not only offers numerous accessible active sites but also enhances electrolyte diffusion and charge transfer. In a 1.0 M KOH electrolyte, the overpotentials for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at 10 mA cm⁻² are 47 mV and 246 mV, respectively, demonstrating remarkable stability over 100 hours and excellent turnover frequency. X-ray photoelectron spectroscopy (XPS) analysis indicated that the formation of the CoMoS2/NiSe2 heterojunction facilitates interfacial electron transfer, thereby optimizing the electronic structure and augmenting the intrinsic catalytic activity. This study presents a viable method for the design of high-performance heterostructured electrocatalysts for efficient water electrolysis through interface engineering and electronic structure modulation.