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 asprepared 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 degrees 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 H-2 evolution of 144 mu mol 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. (C) 2015 Elsevier B.V. All rights reserved.