Fluorinated Oleophilic Electrochromic Copolymer Based on 3-(N-Trifluoroacetamido)thiophene and 3,4-Ethylenedioxythiophene (EDOT)

A new fluorine-containing monomer 3-(N-trifluoroacetamido)thiophene (F-TH) was synthesized and characterized for the first time. Its molecular structure was determined through a single-crystal X-ray study.F-THfunctions as a building block in electropolymerization with 3,4-ethylenedioxythiophene (EDOT) and subsequently gives a novel conjugated copolymerP(F-TH : EDOT). Compared with the parent homopolymer poly(3,4-ethylenedioxythiophene) (PEDOT) film, the sponge-like nanoporousP(F-TH : EDOT) film has a slightly larger band gap with a reduced hydrophilic and increased oleophilic surface. Spectroelectrochemical analysis results reveal thatP(F-TH : EDOT) exhibits excellent electrochromic performances with a higher optical contrast (55 %) and much shorter coloring time (0.70 s) than that ofPEDOT(43 %, 1.54 s). The coloration efficiency value ofP(F-TH : EDOT) achieves up to 167.9 cm(2)/C, 55 % higher than that ofPEDOT (108.1 cm(2)/C). These improved electrochromic properties ofP(F-TH : EDOT) are probably related with the enhanced wettability to electrolyte solution.