Achieving well-ordered microstructure and enhanced conductivities in n-doped conjugated polymers via dual-affinity dopant

Abstract

Doping is a key approach to adjusting the electrical conductivities of polymer devices. However, the disruption to the microstructure of conjugated polymers from counterions of the dopant is the crucial factor limiting performance improvement. Herein, we propose a dual-affinity strategy for dopant design and present a novel n-type dopant, pTAM, with a 2-aminobenzimidazole triaminomethane structure. This pTAM dopant can significantly improve the electrical conductivity of several classic conjugated polymers with a 40%–240% increase in electrical conductivities compared with polymers doped by the widely used dopant 1,3-dimethyl-2-phenylbenzimidazoline (N-DMBI), reaching 83.3 ± 5.1 S cm⁻¹. The enhanced performance is attributed to the matched interaction between pTAM cation and doped conjugated polymer, maintaining a well-ordered microstructure. Our work emphasizes the importance of the dopant-polymer microstructure relationship to the electrical performance, providing a corresponding effective strategy of dopant design for organic electronics and modern semiconductors.