Reversible protonic doping of poly(2,5-bis(5-(2,3-dihydrothieno[3,4-b][1, 4]dioxin-5-yl)-3-dodecylthiophen-2-yl)thieno[3,2-b]thiophene)

Abstract

Herein, a novel conducting polymer poly(2,5-bis(5-(2,3-dihydrothieno[3,4-b][1, 4]dioxin-5-yl)-3-dodecylthiophen-2-yl)thieno[3,2-b]thiophene) has been developed and synthesized via in situ oxidative polymerization using FeCl₃ as the oxidant. This polymer can be proton doped, and the doping process is reversible. The proton-doped film exhibits p-type conduction, with a Seebeck coefficient of ca. 24 µV/K, and an electrical conductivity of ca. 30 S·cm⁻¹ with a carrier density of 2 × 10²⁰ cm⁻³ has been achieved. This work introduces a new approach for designing proton-dopable organic semiconductors: exchanging and modifying the chemical structure to enable precise tuning of the semiconductor’s properties.

Keywords:

• Carrier density
• carrier mobility
• conducting polymers
• doping
• proton

Disclosure statement

There are no conflicts of interest to declare.

Additional information

Funding

This research was funded by the Grant-in-Aid for Scientific Research (B) (No. 21H01911) from MEXT, Japan.