Facile solid solution of trirutile and columbite structured oxides Zn1-xLixNb2-xMoxO6 and Zn1-xLixNb2-xWxO6 (x = 0.0-1.0): synthesis and photocatalytic studies

Abstract

ABSTRACT The present study deals with the synthesis, characterisation and photocatalytic activity studies of coupled substituted columbite and trirutile structured AB2O6 oxides such as columbite structured ZnNb2O6 and trirutile structured LiNbMoO6 & LiNbWO6. Synthesis of solid solution was carried out by standard solid-state method and the products were well characterised by XRD (X-ray diffraction), SEM (Scanning electron microscope), EDAX (Energy dispersive x-ray analysis) and UV-vis DRS (diffused reflectance spectroscopy). XRD analysis revealed that all the compositions showed single phase and for the first time orthorhombic LiNbWO6 structural transformations were identified with the effect of calcination time, respectively. The band gap values of Zn1-xLixNb2-xMoxO6 were in the range of 3.82–3.22 eV, while for Zn1-xLixNb2-xWxO6 were in the range of 3.82–2.76 eV indicating band gap engineering. Furthermore, all the compounds Zn1-xLixNb2-xMoxO6 and Zn1-xLixNb2-xWxO6 showed significant photocatalytic activity towards p-NP (p-nitrophenol) degradation. Thus, this study presented the remarkable photocatalytic activity between columbite structured ZnNb2O6 and trirutile structured LiNbMoO6 & LiNbWO6 of the prepared new solid solution Zn1-xLixNb2-xMoxO6 & Zn1-xLixNb2-xWxO6 for the first time.