Summary: | 碩士 === 國立臺灣海洋大學 === 電機工程學系 === 100 === Zinc tungstate nanopowder (ZnWO4 NP) were successfully prepared by microwave-assisted synthesis and calcinated at different temperatures in the range of 300 − 900 oC. The structural and optical properties of the as-synthesized and calcinated ZnWO4 NPs are investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman scattering, photoluminescence (PL), and time-resolved photoluminescence (TRPL) measurements.
The XRD patterns exhibit significant wolframite structure of ZnWO4 NPs at calcination temperatures above 300 oC FTIR and Raman spectra show respectively, the variation of different absorption and Raman signals as a function of calcination temperature. In addition, the 15 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.
|