Synthesis And Properties Of3DOM Poly(aniline-co-diphenylamine) Eletrochromic Films

Electrochromism is a phenomenon related to optical changes occurring inmaterials by a reversible potential. Polyaniline（PANI）, one of conductingpolymers, has been subject to intensive investigation and wide application dueto its vivide colour changes, high environmental stability, high conductivity andsimple preparation process. In this work, poly（aniline-co-diphenylamine）copolymer film and its3-dimensionally ordered（3DOM） macroporous filmwere prepared by electropolymerization, and their electrochromic propertieswere also studied.The eletrochemical copolymerization voltage of aniline and diphenylaminewas determined by cyclic voltammetry of the comonomers solution. Films in awide composition range of aniline and diphenylamine were prepared in differentcomonomers molar ratio solutions by potentiostatic method. By analysing thecyclic voltammograms of the comonomers solutions,0.8V was chose as thecopolymerization voltage. FTIR transmission spectra of copolymer reflected allkinds of the copolymers contain the characteristic peaks of PDPA and PANI, itmeans the DPA and ANI have been copolymerized. SEM measurement resultsshowed the morphology of copolymer films are controled by both of the growthmechanism of PDPA and PANI, and the roughness of copolymer films arebetween the PDPA film and PANI film. The electrochromic properties ofcopolymer film changed according to the composition range of aniline anddiphenylamine, and when the C_ANI:C_DPD was9:1, the average transmissioncontrast was maximum.3DOM macroporous copolymer films were prepared though colloidalcrystal template-assisted electrochemical deposition method. The prepared filmscontained uniform3DOM macroporous structure,which promotes the diffusioncoefficient of Li+in electrochromic process. Also, the3DOM structurepromoted the transmission contrast, optic density and colouring effience. Finally,the3DOM structure shortened the coloring response time and bleachingresponse time.