Influence of W doped ZrV2O7 on structure, negative thermal expansion property and photocatalytic performance

Abstract Tungsten-doped ZrV2O7 having good photoactivities under UV-light excitation for the degradation of Rhodamine B has been synthesized by sol–gel method. As-prepared samples were examined by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, UV–vis absorption and photoluminescence spectroscopy. From the structural and morphological characterization it has been stated that the presence of W6+ induces the progressive stabilization of normal phase with 1 × 1 × 1 cubic structure (centric space group P a 3 ¯ (Z = 4)). ZrV1.6W0.4O7.2 shows negative thermal expansion (NTE) at room temperature while ZrV2−xWxO7+δ with other ratios show positive thermal expansion. Mechanism for this change in thermal expansion property was discussed. ZrV1.6W0.4O7.2 also exhibits best photocatalytic performance, the reason is that the occurrence of W6+ doping ZrV2O7 system ZrV2O7 system induces the higher photocatalytic activities by promoting the separation of photo-induced electron-hole pairs. PL analysis provides clear evidence of the lower charge carrier recombination in tungsten-doped systems.