Controllable synthesis of WO3·nH2O microcrystals with various morphologies by a facile inorganic route and their photocatalytic activities

Abstract

WO₃·nH₂O microcrystals with different shapes have been synthesized via a facile inorganic hydrothermal route. By controlling the amount of Na₂SO₄ in the precursor solution, hexagonal WO₃·0.33H₂O nanoplates, WO₃ nanorods, and octahedron-shaped WO₃·0.5H₂O crystals have been obtained, highlighting the role of Na₂SO₄ in the growth of WO₃·nH₂O crystals. Based on the experimental observations, we have discussed the growth mechanisms of the WO₃·nH₂O crystals. The adsorption ability and photocatalytic activities of tungsten trioxide hydrates have also been investigated, and the results show that the WO₃·0.33H₂O nanoplates with large surface areas show the largest adsorption ability, and WO₃·0.5H₂O octahedral microcrystals with large bare crystal face exhibit the highest photodegradation performance in these samples, rendering their potential application in the treatment of organic pollutants.