An electrochromic device based on all-in-one polymer gel through in-situ thermal polymerization

A self-standing all-in-one electrochromic gel utilizing phenyl viologen (PV) and N,N,N',N'-tetramethyl1,4-phenylenediamine (TMPD) as the electrochromic materials is prepared by incorporating a thermocured cross-linked polymer matrix. The thermal-cured polymer matrix can prevent the agglomeration of PV happening on the electrode surface, resulting in the excellent write-erase ability of the obtained gelated ECD. Moreover, the cross-linker which possesses the long propoxylated arms leads to the easier diffusion for both PV and TMPD in the obtained polymer network. As a result, the obtained ECD exhibits a large transmittance change (Delta T > 67% at 620 aim) within a short response time (<3.5 s) under an extremely low driving voltage (0.5 V). Besides, this device remains over 55% of Delta T after 10,000 cycles of switching. (C) 2015 Elsevier B.V. All rights reserved.