Effects of different dopants on the band gap and electrical conductivity of the poly(phenylene-thiazolo[5,4-d]thiazole) copolymer
By Olgun, U. & Gulfen, M.
Published in RSC Adv.
The Royal Society of Chemistry
2014
Abstract
Poly(phenylene-thiazolo[5, 4-d]thiazole) (p-PhTT) is an alternating copolymer having semiconductivity and low band gap energy. In this study, p-PhTT polymer was synthesized by the reaction of terephtalaldehyde and rubeanic acid (dithiooxamide). The synthesized p-PhTT was doped with different chemical agents such as HCl, Cu(ii), Fe(iii), H3BO3 and I2. The doped p-PhTT polymer samples were examined by using UV-vis, FT-IR, cyclic voltammetry (CV) and electrical conductivity. The optical (Eoptg) and electrochemical (ECVg) band gap energies of undoped p-PhTT were calculated as 2.56 and 2.50 eV from the UV-vis and CV measurements, respectively. The Fe(iii) doping decreased the ECVg energy of the p-PhTT polymer from 2.50 to 2.35 eV according to the CV data. The other dopants increased the band gap energy of the polymer above 2.50 eV. The electrical conductivities of p-PhTT polymers were also measured. It was found that the Fe(iii) doping of p-PhTT increased the electrical conductivity from 0.35 to 12 [small mu ]S cm-1.