Low thermal expansion, phase transition and luminescence properties of ZrxAl2-xMo3-xVxO12

In the study, a novel ZrxAl2-xMo3-xVxO12 material was prepared by the traditional solid synthesis method and showed the low thermal expansion in a large temperature range. ZrxAl2-xMo3-xVxO12 had the strong broad-band luminescence characteristics almost in the whole visible region. The coefficient of thermal expansion, phase transition, and anisotropy of ZrxAl2-xMo3-xVxO12 were explored with Raman spectrometer, dilatometer and X-ray diffractometer. The results showed that when x was less than 0.5, the solid solution existed in the form of single phase ZrxAl2-xMo3-xVxO12. When doping ions were further increased, ZrMo2O8 and Al2Mo3O12 were formed. The monoclinic-to-orthorhombic phase transition temperature of ZrxAl2-xMo3-xVxO12 could be well tailored by changing the contents of Zr4+ and V5+. The samples were crystallized in a monoclinic structure group of P2(1)/a (No. 14) when x <= 0.5 at room temperature. Doping Zr4+ and V5+ ions endowed the material with the better LTE property and the strong broad-band luminescence almost in the whole visible region. Its low expansion and light properties in a wide temperature range suggested its potential applications in LED and other optoelectronic devices.