Luminescence Mechanism of ZnWO4 Nanopowder Synthesized by Microwave-Assisted Heating

The luminescence investigations on the calcinated zinc tungstate nanopowder (ZnWO₄ NP) synthesized by microwave-assisted synthesis are presented using photoluminescence (PL) and time-resolved photoluminescence (TRPL) analyses. The X-ray diffraction (XRD) patterns exhibit that the significant wolframite structure of ZnWO₄ NP can be detected at calcination temperatures above 300 ^oC. The 12 K PL and TRPL results demonstrated that the deformation of WO₆ octahedra is responsible for the low-energy side of PL spectra and dominate the red-shifted PL spectra with increasing calcination temperatures.