Microwave–assisted synthesis of nanoscale tungsten trioxide hydrate with excellent photocatalytic activity under visible irradiation.

Tungsten trioxide hydrate (WO 3 ⋅1/3H 2 O) nanoparticles (NPs) were prepared and applied in visible–light–driven photocatalysis for organic dye degradation. • WO 3 ⋅1/3H 2 O nanoparticles were prepared via a microwave–assisted synthetic pathway. • The WO 3 ⋅1/3H 2 O showed enhanced photocatalytic dye degradation capacity. • The WO 3 ⋅1/3H 2 O exhibited excellent stability and reusability. Tungsten trioxide hydrate (WO 3 ⋅1/3H 2 O) nanoparticles (NPs) were prepared via a microwave–assisted synthetic pathway by using Na 2 WO 4 ·2H 2 O and PdCl 2 as precursors. Microstructure and morphology of as–prepared WO 3 ⋅1/3H 2 O NPs were investigated through X–ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FT–IR) spectra, while porosity and bandgap through specific surface area and UV–vis absorption spectroscopy. It was found that Pd2+ ions played a crucial role in the formation of WO 3 ⋅1/3H 2 O NPs, and thus a possible formation mechanism was proposed based on the growth processes. The photocatalytic property of WO 3 ⋅1/3H 2 O NPs was evaluated on the basis of Rhodamine B (RhB) degradation in aqueous solutions under simulated visible irradiation. Photocatalytic experimental results indicated that as–prepared WO 3 ⋅1/3H 2 O NPs exhibited much more superior photocatalytic activity by contrast to that of the commercial WO 3. [ABSTRACT FROM AUTHOR]