Complementary electrochromic device using metal grid electrode structure

• Main Authors: Chun-ming Chiu, 邱俊銘
• Other Authors: Ying-Chung Chen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/nmc68b

碩士 === 國立中山大學 === 電機工程學系研究所 === 103 === In this study, the electrodes for the complementary electrochromic device (CECD) were fabricated using cooper, nickel-vanadium and tungsten by pulsed-DC sputtering deposite on and formed the metal grid structure by self-made mask. Then, the electrochromic films of NiO and WO3 were respectively deposited on these electrodes by e-beam evaporation. Finally, these electrodes were applied to CECDs with gel polymer electrolyte. This study sequentially investigated the stability of high-temperature environment and electrochemical circulation, uniformity of the simulated electric field and the effect on the device characteristics with or without metal grid structure. The first part of the experimental results is the characteristics of the metal electrode. When the environment temperature rising to 100 ℃, the sheet resistances of the W, Ni-V and Cu were rised less than 5 %. For the stability of the electrochemical part, the CECD was fabricated with metal electrodes and switched 50 times with ± 1.8 V. The results reveal that the attenuation of the consumed charge of devices with Cu and Ni-V is 14 % and W is the lowest with 8 %. Consequently, the metal W exists the highest electrochemical stability. For the uniformity of the simulated electric field part, the uniformity of the electric field was enhanced by using metal grid structure and the more uniform electric field received by using Cu grid due to its excellent conductivity. For the fabrication and the analysis of CECD, the CECD exhibited better electrochromic characteristics when the applied voltage is 1.8 V. When the applied time of CECD is 60 s, the experiment results (λ@550 nm) show that the transmittance of colored state is 36.17 %, transmittance change (ΔT%) is 36.16 % and the coloration efficiency (η) is 77.92 cm2/C. The CECD using W grid electrode structure (W-CECD) exhibited better electrochromic characteristics when the applied time is 60 s. The experiment results (λ@550 nm) show that the transmittance of colored state is 32.46 %, ΔT% is 39.08 % and η is 81.93 cm2/C. The CECD using Cu grid electrode structure (Cu-CECD) exhibited better electrochromic characteristics when the applied time is 30 s. The experiment results (λ@550 nm) show that the transmittance of colored state is 36.73 %, ΔT% is 36.67 % and η is 29.62 cm2/C. For the response time and the memory effect, the response time of the CECD was found to be about 94 s and the transmittance of colored state increased to 36.35 % after 24 h without biased voltage supply. The response time of the W-CECD was found to be about 98 s and the transmittance of colored state increased to 33.31 % after 24 h without biased voltage supply. The results show that the memory effect was still excellent after using metal grid electrode structure.