The effect of solvents and organic acids on the p-doping behaviors of poly(3′,4′-Ethylenedioxy-2,2′:5′,2″-terthiophene)

Poly(3′,4′-Ethylenedioxy-2,2′:5′,2″-terthiophene) was synthesized by chemical oxidative polymerization of 3′,4′-Ethylenedioxy-2,2′:5′,2″-terthiophene using FeCl 3 as an oxidant. The resulting polymer was characterized by FTIR and 1 H NMR. p-doping behaviors of substituted polyterthiophene with different organic sulfonic acids (methanesulfonic acid, p -toluene sulfonic acid, and β-naphthalene sulfonic acid) in different solvents (CH 3 CN, CHCl 3 , THF and DMF) were studied by UV-VIS spectroscopy. The results from structural characterizations showed that the α,α′-bonding predominates in polyterthiophene. The spectroscopic changes in UV-VIS showed that β-naphthalene sulfonic acid was an efficient doping acid for polymer while varying the solvents. Meanwhile, CH 3 CN showed a high efficiency for p-doping of polyterthiophene while varying the doping acids.