Graphite coated by Cu2S‐Cu2O nanoparticles film for hydrogen production application

Many researchers have shifted their interest towards eco‐friendly, cost effective, and environmental‐based metal oxide nanoparticles. Herein, Cu 2 O nanoparticles are synthesized via green method for water splitting application. The prepared materials are characterized structurally and morphologically by field emission‐scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X‐ray photoelectron spectroscopy (XPS) Raman, and UV–visible spectroscopy. It is found that size and morphology depend strongly on OLE concentration and reaction time. The temperature increase leads to the formation of copper oxide (CuO) nanoparticles, which exhibit quantum confinement behavior and have an optical band gap that increases with decreasing size. Photoelectrochemical (PEC) tests of the coated graphite with Cu 2 O nanoparticles show a severe instability of Cu 2 O under irradiation due to the oxidation state that can easily change. For that, a protective overlayer of cuprous sulfide Cu 2 S is successfully grown on the top of Cu 2 O nanostructures to stabilize the photocathode. After Cu 2 S deposition, the measured photocurrent is significantly improved. Thus, this material is very promising for hydrogen generation by water splitting.