Acanthosphere-like bimetallic sulfide Cu9S5/Mo2S3/NF as bifunctional catalyst for water splitting

Abstract

Reducing the overpotential of water splitting is an important strategy for achieving low-cost and large-scale production of hydrogen (H2) and oxygen (O2). It is shown that bimetallic sulfide combines the advantages of a single component and an ideal structure for efficient electrocatalysis. Hence, an acanthosphere-like bimetallic sulfide electrocatalyst Cu9S5/Mo2S3/NF with high catalytic performance and superior durability was prepared by a simple one-pot method. In the oxygen evolution reaction (OER), the Cu9S5/Mo2S3/NF achieved a Tafel slope of 62.7 mV dec-1, and an overpotential of 224 mV at a current density of 10 mA cm−2. Concomitantly, it also possesses a small overpotential of 96 mV at 10 mA cm−2 and low Tafel slope of 81.6 mV dec-1 at the used of hydrogen evolution reaction (HER) catalyst. Moreover, the two-electrode system Cu9S5/Mo2S3/NF||Cu9S5/Mo2S3/NF single cell requires only 1.55 V to achieve a current density of 10 mA cm−2 in overall water splitting. This work highlights the advantages of bimetallic sulfide combines structural for overpotential of water splitting and provides an idea for modifying the catalytic performance of single metal sulfides and preparing high-performance bimetallic sulfide catalysts.