Hydrothermal synthesis of WO₃ nanowires in the presence of guanidine sulfate and its photocatalytic activity

Abstract

WO₃ nanowires were fabricated by a hydrothermal method, which proceeded at 170 °C for 48 h in a solution containing C₂H₁₀N₆H₂SO₄ as a dispersant and Na₂WO₄ as a starting material. The nanowires exhibit a well crystallized one-dimensional structure with 20 nm in diameter and several microns in length. The physicochemical properties of WO₃ were compared using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and UV-vis spectroscopy (UV-Vis). The photoactivity of the as-perpared WO₃ nanowires was evaluated through the photodegradation of methylene blue (MB) in aqueous solution. The experimental results demonstrate that addition of C₂H₁₀N₆H₂SO₄ salt in the WO₃ nanowires synthesis process can enhance its photocatalytic activity obviously.

Keywords

hydrothermal method / WO₃ nanowires / crystal structure / photocatalytic

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