Study of Porous WO3 Thin Film Using Electrochemical Etching Method

• Main Authors: Yen-ChenChen, 陳彥臻
• Other Authors: Kuan-Zong Fung
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/30129298226441808944

碩士 === 國立成功大學 === 材料科學及工程學系碩博士班 === 98 === In recent years, the crisis of energy was happened. Environment consciousness began to rise and looking for alternative sources of energy also reduce energy consumption. One of option is Electrochromic Device. Decreasing the light illuminate into the building make the air-condition increasing the efficiency. The porous WO3 was heat treatment at 450℃ and electrochemical etching in NaF solution.NaF was a kind of water-soluble electrolyte. The parameter in this research adjusted the concentration and reactive time. The electrochemical etching reaction worked in 5℃ at an constant voltage for decreasing the heat accumulation which makes the device damage. The electrolyte device was LiClO4+PC. The experiment result shows WO3 after heat treatment at 450℃.The optical properties about transmittance ratio of the device was 67.19%.The WO3 after electrochemical etching became porous WO3 and transmittance ratio of the device was 54.38%.The Optical Density of WO3 without electrochemical etching was better than WO3 which after electrochemical etching and optical density from 0.92 to 0.38.The reason of this Phenomenon was WO3 after electrochemical etching the thickness of thin film became decrease. In voltammograms test of WO3 which after electrochemical etching had porous structure became more stability. The result shows WO3 without effect of structure that device had irreversible reaction happened. It would decrease the life of device.In voltammograms test also could calculate the current of non electrochemical etching WO3 and electrochemical etching WO3 were (65.28mA)/( 6.15mA). The color efficiency of Electrochromic device could calculate by current density and optical density.The color efficiency of WO3 without electrochemical etching and WO3 with electrochemical were (15cm2C-1) /(61.38cm2C-1).The responsive time test show a device supply an constant voltage in 100 seconds observe the device transformation. The transmittance of WO3 without any action was better than porous WO3. The device of porous WO3 could be fast to reach rate-determining-step.