Superior optical properties of Fe3+–W18O49 nanoparticles prepared by solution combustion synthesis

Abstract

Modification by metal-doping allows the design of new nanomaterials with enhanced optical properties. In this paper, the photocatalytic effects of Fe³⁺-doped W₁₈O₄₉ nanorods prepared by solution combustion synthesis were studied for the first time. The Fe³⁺-doped W₁₈O₄₉ powders were investigated by X-ray diffraction, high-resolution transmission electron microscopy, selected area electron diffraction, and X-ray photoelectron spectroscopy. The powders were well-crystalline with diameters ranging from 50 nm to 250 nm and the length decreasing from more than 10 μm to 4 μm on average. The photoluminescence (referred to as PL here after) spectrum showed that the emission intensity increased with increasing Fe³⁺ doping, suggesting that more defects were generated. Moreover, this novel composite catalyst displayed excellent photocatalytic efficiency towards the degradation of organic compounds in aqueous media under UV-visible light irradiation. In particular, 0.5 wt% Fe³⁺-doped W₁₈O₄₉ had the best photocatalytic efficiency. This improvement was mainly attributed to the synergistic effect between Fe³⁺ and W₁₈O₄₉ nanopowders and the defects in the nanostructure caused by doping.