A spectroelectrochemical study of poly(dithienothiophenes)

The use of n- and p-dopable conjugated polymers as both the working and counter electrodes in an electrochemical device has always attracted chemists and has stimulated the design of new molecules with a low energy gap that can be p- and n-doped efficiently. The present paper reports the spectroelectrochemical study of polymers obtained from several dithienothiophene isomers, molecules with three thiophene rings fused in different positions. Of the six isomers, poly(dithieno[3,4-b:3',2'-d]thiophene) and poly(dithieno[3,4-b:2',3'-d]thiophene) were tested against poly(dithieno[3,2-b:2',3'-d]thiophene) and poly(dithieno[3,4-b:3',4'-d]thiophene). The differences in their performance, related to the geometry of the starting molecules and to enchainment, are reported and discussed.