A facile preparation of crystalline GeS2 nanoplates and their photocatalytic activity

Crystalline GeS2 nanoplates were prepared by low temperature solvothermal process and characterized with X-ray diffraction, transmission electron microscopy, energy-dispersion X-ray analysis, X-ray photoelectron spectroscopy, nitrogen adsorption, Raman spectroscopy, FT-IR spectroscopy and UV–vis–NIR diffuse reflectance absorption spectroscopy. Photocatalytic hydrogen evolution from water over the as-prepared GeS2 nanoplates was explored using Na2S and K2SO3 as sacrificial reagents. The results indicate that the crystalline orthorhombic GeS2 nanoplates can be obtained at 140 °C using this simple method and acetic acid as the solvent plays an important role in the formation of the GeS2 nanoplates. More importantly, the as-prepared GeS2 nanoplates can serve as a potential photocatalyst with a rate of H2 evolution of 144 μmol g−1 h−1 for hydrogen production from water when a xenon lamp is used as a light source. In addition, the formation mechanism of GeS2 nanoplates was preliminarily discussed.