Tuned structures and enhanced photoluminescence of WO3-x nanomaterials by TiO2

Abstract

Different structured WO3-x nanomaterials were synthesized in ethanoic acid using the WCl6 and Ti(OC4H9)4 precursors. Advanced characterizations reveal that the incorporation of TiO2 leads to the granulation and structural conversion of WO3-x due to the reduction of surface tension on the WO3-x nanoparticles (NPs) and the fast nucleation of the WO3-x NPs caused by the adsorption of Ti(OC4H9)4 molecules on the WO3-x NPs. The photoluminescence (PL) studies indicate that the WO3-x − TiO2 hybrid nanomaterials generate ultraviolet, blue, green, red and near-infrared emissions, and that the PL emission is remarkably enhanced. The emissions can be attributed to the band − band, defect state − state and defect level − band transitions. The substantial PL enhancement originates from trapping the strong PL emission from TiO2 by the WO3-x nanomaterials.