| 초록 |
The interfacial adsorption structure of the dopants onto the surface of carbon nanotube (CNT) is directly related to the thermoelectric (TE) properties of CNTs by controlling the charge transfer behavior. Herein, we introduce an imidazolium-based ionic liquid as a dopant of CNTs and investigate doping mechanisms at different CNT surface states. The imidazolium cations are selectively adsorbed at the negatively charged CNT surface, forming the cation-rich layer nearby the CNT surface. In contrast, at the relatively neutral CNT surface, more tetrafluoroborate anions can easily access the CNT surface. The distinctive molecular adsorptions are selectively controlled using a simple solution process and the different doping characteristics are observed that p-doping by the former case and n-doping by the latter case. Finally, optimized CNT films exhibit high p-type TE power factors up to 762 μW m−1 K−2 and a flexible TE generator is successfully fabricated showing the output power of 6.8 μW and voltage of 334 mV. |
