Affiliation:
1. Department of Organic and Nano System Engineering Konkuk University Seoul 05029 Korea
2. Department of Materials Engineering and Convergence Technology Gyeongsang National University Jinju 52828 Republic of Korea
3. Institute of Advanced Composite Materials Korea Institute of Science and Technology (KIST) Jeonbuk 55324 Republic of Korea
4. Department of JBNU-KIST Industry-Academia Convergence Research Jeonbuk National University (JBNU) Jeonbuk 54896 Republic of Korea
Abstract
Doping of conjugated polymers (CPs) is a promising strategy to obtain solution‐processable and highly conductive films; however, the improvement in electrical conductivity is limited owing to the relatively poor carrier mobility of CPs. Herein, a CP with excellent molecular doping ability, i.e., poly[2‐([2,2'‐bithiophen]‐5‐yl)‐3,8‐difluoro‐5,10‐bis(5‐octylpentadecyl)‐5,10‐dihydroindolo[3,2‐b]indole] (PIDF‐BT) is wrapped onto the surface of single‐walled carbon nanotubes (SWCNTs). The resulting PIDF‐BT@SWCNT simultaneously achieves excellent solution dispersibility and a high electrical conductivity of over 5000 S cm−1 through AuCl3 doping. The doping mechanism is systematically studied using spectroscopic analysis, and the four‐probe field‐effect transistor based on the doped PIDF‐BT@SWCNT confirms a carrier mobility up to 138 cm2 V−1 s−1. The carrier‐transfer barrier energy is related to the Schottky barrier between the SWCNT and PIDF‐BT, which can be controlled by doping. Finally, when the doped PIDF‐BT@SWCNT is applied to a thermoelectric device, a power factor exceeding 210 μW m−1 K−2 is achieved because of its high electrical conductivity, even if the increased carrier density reduces the Seebeck coefficient.
Subject
General Earth and Planetary Sciences,General Environmental Science