Correlation Between the Electrochromic Properties and the Electronic/Atomic Structures of Li:WO3 Studied by X-ray Absorption Spectroscopy

• Main Authors: Jiun-Shuen Chen, 陳鈞順
• Other Authors: Way-Faung Pong
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/12775588332919360874

碩士 === 淡江大學 === 物理學系碩士班 === 101 === In-situ x-ray absorption spectroscopy of three different types of tungsten oxide thin films were performed to study the electronic structure of the films with repetitive cycles of coloration and bleaching process. In-situ W L3-edge x-ray absorption near edge spectroscopy (XANES) of crystalline and nanocrystalline tungsten oxide films showed that with the coloration the intensity of the spectra decreases and it increases with bleaching, which corresponds to the filling and unfilling of the density of the conduction band, respectively. After repeated cycles of coloration and bleaching the structural disordering was observed from the second derivative of W L3-edge XANES spectra. In-situ extended x-ray absorption fine structure spectra reveal that the atomic structure of the samples remain unaltered after coloration and bleaching. The nanocrystalline tungsten oxide film showed recovery of (~ 97 %) electronic and atomic structure after the first cycle of coloration and bleaching, which was substantially higher compared to other two crystalline samples. It reveals that nanocrystalline sample has superior electrochromic properties than crystalline samples.