Photocatalytic O2 production using WO3 nanoparticles prepared by annealing ethylenediamine tungstate/CxNy gel

Abstract

WO₃ nanoparticles have extraordinary potential applications in water oxidation and degradation of organic pollutes. In this paper, we reported a strategy for the synthesis of nano-sized WO₃ particles by annealing ethylenediamine tungstate ((ET)/C_xN_y) gel, which was prepared by condensing (NH₄)₁₀(H₂W₁₂O₄₂)·4H₂O, (CH₂NH₂)₂ and CCl₄. The as-synthesized WO₃ nanoparticles were characterized by X-ray diffraction, X-ray photon energy spectroscopy, UV-vis diffuse reflection spectroscopy, photoluminescence, and transmission electron microscopy. The as-synthesized spherically shaped WO₃ nanoparticles with sizes of 50–100 nm have high crystallinity and few defects. The photocatalytic performance of the as-synthesized WO₃ nanoparticles was tested as O₂ evolution from water in the presence of KIO₃ as an electron sacrifice reagent. The rate of O₂ evolution from water on the as-synthesized WO₃ nanoparticles is more than two times higher than that of WO₃ derived from annealing ammonium tungstate and is 3.7 times higher than that of commercial WO₃. We believe that the WO₃ nanoparticles synthesized by this method are promising candidates for application as photocatalytic O₂ production systems.