One-pot synthesis of non-noble metal WS2/g-C3N4 photocatalysts with enhanced photocatalytic hydrogen production

Abstract

As an increasing number of photocatalysis are developed, non-noble metal photocatalysts that can be synthesized from earth-abundant and low-cost materials have received a great deal of attention. In this study, non-noble metal WS2/g-C3N4 photocatalysts were prepared by a facile one-pot synthesis. Varying masses of tungsten disulfide (WS2) were successfully loaded onto g-C3N4 and characterized by X-ray diffraction (XRD), inductively coupled plasma optical emission spectrometry (ICP-OES), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). These results indicated that the WS2 was successfully synthesized and immobilized closely on the surface of g-C3N4 to form a sheet-like nanostructure. The H2 generation results showed that the optimal photocatalyst was 0.3-WCN because it had the highest photocatalytic H2 production of 154 μmol h−1g−1, which is 34 times higher than bare g-C3N4 and even higher than 0.3 wt% platinum-loaded g-C3N4. Additionally, the possible mechanism of the photocatalyst was studied by photoluminescence (PL), UV–vis diffuse reflectance spectroscopy (UV–vis DRS) and photoelectrochemical tests, which showed that the WS2 played a key role in improving the efficiency of separation and migration of the photogenerated carriers in g-C3N4.