Enhancement of Doping Efficiency of Conjugated Polymers via Backbone Torsion Strategy with Methyl Group Introduction for High-Performance Organic Thermoelectrics
발표자
장규진 (한국화학연구원)
연구책임자
한미정 (한국화학연구원)
초록
내용
Chemical doping of conjugated polymers (CPs) enhances their electrical properties by increasing free carrier concentration, necessitating structural designs that facilitate efficient dopant incorporation into the polymer backbone. For large molecular dopants such as F4TCNQ, sufficient internal space within the polymer is necessary for effective diffusion of dopants. In this study, we synthesized a series of CPs (DPP-BT, DPP-MBT, MDPP-BT and MDPP-MBT) with different methylation patterns on the donor and acceptor units to induce backbone torsion and ensure effective access spaces for dopants. The position and number of the methyl groups affected both crystallinity and doping characteristics of the CPs. As a result, MDPP-MBT, which exhibited the highest backbone torsion, achieved a conductivity of 592 S cm⁻¹ and a power factor of 1284 μW m⁻¹ K⁻² upon doping with 0.1wt% of F4TCNQ, representing more than a twofold enhancement over the non-methylated DPP-BT.