Synthesis of reduced cubic phase WO3-x nanosheet by direct reduction of H2WO4•H2O

The cubic phase WO3-x with two-dimensional nanosheet structure is prepared at a relative low temperature through thermal decomposition method. The starting material and decomposition environment are the key factors to obtain the cubic phase WO3-x. The cubic crystal structure is stabilized by the large amounts of oxygen vacancies. The dark blue cubic WO3-x exhibits electrocatalysis performance for hydrogen evolution reaction (HER) in acidic solution (an overpotential -294 mV at the current density of 10 mA/cm(2)). The cubic phase WO3-x shows good photothermal stability with eminent photothermal conversion effect (photothermal conversion efficiency is 48.7% at 808 nm). (C) 2017 Elsevier Ltd. All rights reserved.