Electrochromic polymer achieving synchronous electrofluorochromic switching for optoelectronic application

Overview on the Recent Progress on Electrofluorochromic Materials and Devices: A Critical Synopsis

“…Liu et al proposed the introduction of a biphenyl group into the polythiophene backbone, which is able to form a twisted configuration preventing detrimental exciton interaction in the aggregation states. [101] Effectively, a yellow fluorescence is detected that is quenched with the application of an increasing oxidative potential. The fluorescence recovery without band shift, clearly indicates that the quenching mechanism is caused by the production of the , respectively.…”

“…Liu et al proposed the introduction of a biphenyl group into the polythiophene backbone, which is able to form a twisted configuration preventing detrimental exciton interaction in the aggregation states. [ 101 ]…”

Electroluminochromic Materials: From Molecules to Polymers

“…Solid thin films of P22 emit strong yellow fluorescence due to AIE properties induced by TPE, and upon electrochemical oxidation, this fluorescence was quenched, as shown in Figure 21a, due to oxidation selectively occurring at TPE moieties to become radical cations [75]. Xu et al then reported a series of polymers P23a , P23b , P23c , P24a , and P24b in which ProDOT was copolymerised with 1,1′-biphenyl-4-oxy-functionalized ProDOT, 1,1′-biphenyl, fluorene, stilbene, and 1,2-diphenylfumaronitrile, respectively [76,77]. For the first series of polymers, P23a – P23c , only P23b with biphenyl groups exhibit solid state fluorescence due to AIE effect resulted from intramolecular rotation and conformational twisting.…”

“…For the first series of polymers, P23a – P23c , only P23b with biphenyl groups exhibit solid state fluorescence due to AIE effect resulted from intramolecular rotation and conformational twisting. Upon increasing an applied positive potential from −1 to 1.6 V, bright yellow fluorescence of P23b gradually faded to darkness (Figure 21b) with a transmittance change of 35%, possibly due to the formation of radical cations [76]. Incorporating stilbene and 1,2-diphenylfumaronitrile co-monomers into P24a and P24b , respectively, leads to forming C–H … π interactions between neighbouring polymer chains, making it useful in avoiding undesirable exciton interactions in the aggregation state.…”

“…Photographs and photoluminescence spectra of EC/EFC devices containing P22 ( a ); P23b ( b ); P24a and P24b ( c ); and P25a – d ( d ) showing photoluminescence quenching upon undergoing electrochemical oxidation from the neutral to oxidised states. Reproduced with permission from [75] ( a ), [76] ( b ), [77] ( c ) and [78] ( d ). Copyright 2015, the American Chemical Society ( a ); 2017 and 2018, Elsevier B. V. ( b , c ); and 2017, the Royal Society of Chemistry.…”