An efficient method to modulate the structure, morphology and properties of WO3 through niobium doping

Doped tungsten oxide has been reported to provide enhanced photocatalytic and photoelectronic properties in catalyst and smart window applications. Here Nb-doped WO3 was synthesized to investigate the effect of doping on composition, structure and optical properties. It is shown that niobium ion implantation in WO3 structure results in the morphological evolution from nanosheet into nanoparticle. 5 at% niobium ion doping induces the phase transformation from monoclinic γ-WO3 to monoclinic ε-WO3. UV-vis spectrum shows that niobium implantation results in the increase of the band gap and the shift of absorption edge. Photoelectric measurement indicates that photocurrent increases firstly and then decreases under UV irradiation. The results reported in this study will be useful in formulating optimum doping process to enhance desired photoelectric properties.