Synthesis and thermopower of poly(3-methoxythiophene-2,5-diyl-co-3,4-ethylenedioxythiophene-2,5-diyl)/tosylate

- A novel conducting polymer was synthesized by oxidative in situ polymerization.
- This polymer showed electrical conductivity of 10 S/cm and a carrier mobility of 0.6 cm2/(V s).
- This polymer showed a higher Seebeck coefficient compared with PEDOT/tos.

A novel conducting polymer, Poly(3-methoxythiophene-2,5-diyl-co-3,4-ethylenedioxythiophene-2,5-diyl]/tosylate (P1/tos), was synthesized by oxidative in situ polymerization using Fe(tos)3 as an oxidant. Compared with poly(3,4-ethylenedioxythiophene) (PEDOT), P1 has a deeper HOMO level and a wider energy gap as observed by ultraviolet-visible spectroscopy and photoelectron yield spectroscopy. P1/tos showed electrical conductivity of 10 S/cm and a carrier mobility of about 0.6 cm2/(V s), which was extracted by using ion-gel thin film transistors. The calculated carrier concentration was on the order of 1020 cm−3, which is lower than that of PEDOT/tos. The Seebeck coefficient of P1/tos was higher than that of PEDOT/tos.