| 초록 |
The development of n-type conjugated polymer is required for construction of organic thermoelectric (OTE). To induce facile n-type doping, the polymers should have deep LUMO levels (＜-4.0 eV). Acceptor–acceptor-type conjugated polymers (A-A polymers) are potential candidates to attain the LUMO levels. However, imposing a functional group on the electron deficient aromatic structure makes synthesizing the structures quite challenging. In the present study, A–A polymer, PDPP-NDI, was synthesized by Stille coupling of distannylated DPP and dibrominated NDI. The alternating DPP and NDI moieties ensured sufficiently deep LUMO energy level of -4.4 eV, suitable for n-type doping with N-DMBI. The doped PDPP–NDI exhibited n-type TE properties, with an average electrical conductivity and power factor of 1.16 × 10-3 S cm-1 and 1.82 × 10-3 μW m-1 K-2, respectively. Moreover, the doped PDPP-NDI was changed to p-type thermoelectric properties at high doping ratios over 30%. |
