Rapid Microwave-Assisted Synthesis of ZnIn(2)S(4) Nanosheets for Highly Efficient Photocatalytic Hydrogen Production

In this study, a facile and rapid microwave-assisted synthesis method was used to synthesize In(2)S(3) nanosheets, ZnS nanosheets, and ZnIn(2)S(4) nanosheets with sulfur vacancies. The two-dimensional semiconductor photocatalysts of ZnIn(2)S(4) nanosheets were characterized by XRD, FESEM, BET, TEM, XPS, UV–vis diffuse reflectance, and PL spectroscopy. The ZnIn(2)S(4) with sulfur vacancies exhibited an evident energy bandgap value of 2.82 eV, as determined by UV–visible diffuse reflectance spectroscopy, and its energy band diagram was obtained through the combination of XPS and energy bandgap values. ZnIn(2)S(4) nanosheets exhibited about 33.3 and 16.6 times higher photocatalytic hydrogen production than In(2)S(3) nanosheets and ZnS nanosheets, respectively, under visible-light irradiation. Various factors, including materials, sacrificial reagents, and pH values, were used to evaluate the influence of ZnIn(2)S(4) nanosheets on photocatalytic hydrogen production. In addition, the ZnIn(2)S(4) nanosheets revealed the highest photocatalytic hydrogen production from seawater, which was about 209.4 and 106.7 times higher than that of In(2)S(3) nanosheets and ZnS nanosheets, respectively. The presence of sulfur vacancies in ZnIn(2)S(4) nanosheets offers promising opportunities for developing highly efficient and stable photocatalysts for photocatalytic hydrogen production from seawater under visible-light irradiation.