Preparation of WO3/g-C3N4/Cu2O nanocomposite and study its application as catalyst in hydrogen evolution reaction by photocatalytic water splitting

In the present work, WO3/g-C3N4 and WO3/ g-C3N4/Cu2O nanocomposites containing tungsten trioxide and copper (I) oxide nanoparticles were synthesized on a graphitic carbon nitride substrate. The structural and morphological characteristics of the synthesized nanostructures were investigated by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and diffuse reflection spectroscopy (DRS). The performance of nanocomposites as cathodic catalysts was investigated and compared in the photocatalytic water splitting process. The results showed that the WO3/g-C3N4/Cu2O nanocomposite produces the highest current density and the lowest overvoltage in the hydrogen evolution reaction. This improvement in photoelectrochemical performance can be attributed to the increase in surface area and electron transfer due to the synergetic effect between carbon substrate and oxide nanoparticles. In addition to practical studies, the WO3/g-C3N4/Cu2O nanocatalyst was simulated with Materials Studio software and the XRD pattern and its electronic structure were compared with the practical results. The theoretical XRD pattern showed good agreement with the experimental XRD pattern. Accordingly, the proposed nanocomposite can be well used as a cathodic catalyst in the production of pure hydrogen fuel.