Printed Flexible Solid State Electrochromic Devices Based on NiO/WO3 Complementary Electrodes

Tuesday, 26 May 2015: 08:40
Conference Room 4E (Hilton Chicago)
G. Cai, P. Darmawan, M. Cui, and P. S. Lee (School of Materials Science and Engineering, Nanyang Technological University)
In this paper, flexible solid state electrochromic devices based on NiO/WO3 complementary electrodes and gel polyelectrolyte was successfully prepared for transmissive electrochromic applications. The cathode of WO3 film and the anode of NiO film were prepared by inkjet printing, with gel polyelectrolyte as the Li+ion conductor layer. Inkjet printing is a low-cost and attractive technology for patterning electrochromic materials on various substrates and allows deposition of electrochromic materials on a specific location with simultaneous thickness control by the number of printed layers. The printing has been done on flexible transparent conductive electrodes such as indium tin oxide-(ITO) coated polyethylene terephthalate (PET), which overcomes the heavy and rigid drawbacks of ITO glass substrates. In addition, using a gel electrolyte avoids electrolyte leakage problem, allows the ease of handling reduces the cost of device packaging and attains greater reliability. The flexible device exhibits a large optical modulation, fast switching speed and high coloration efficiency.