Cu-doped Ni3S2 electrocatalyst for glycerol oxidation coupling to promote hydrogen evolution reaction

Abstract

Hydrogen energy is becoming increasingly important as a clean and efficient form of energy. Glycerol oxidation synergistic electrocatalytic hydrogen evolution technology is an electrochemical process that integrates anodic glycerol oxidation reaction (GOR) and cathodic hydrogen production. Compared with the oxygen evolution reaction (OER) required in the electrolysis of water for hydrogen production process, this technology can not only reduce the energy consumption of the whole reaction, but also obtain valuable by-products while producing hydrogen. In this study, we successfully prepared a copper-doped Ni3S2 (Cu-Ni3S2@NF) electrode material loaded on a nickel foam carrier by a two-stage hydrothermal synthesis method, and applied it to the bifunctional electrocatalytic reaction of GOR and hydrogen evolution reaction (HER). After a series of in-depth electrochemical performance tests, it was confirmed that 0.1Cu-Ni3S2@NF showed lower overpotential requirements when performing GOR and HER, requiring only 1.41 V relative to the reversible hydrogen electrode (RHE) to drive a current density of 100 mA cm−2 for GOR, and only 0.56 V vs. RHE to achieve the same current density for HER. Moreover, the electrode material still maintains good stability under long-term operation. Among them, the Faraday efficiency (FE) of glycerol oxidation to formate is more than 85 %, while the FE of HER is not less than 93 %.