Efficient strategies for improving the performance of EDOT derivatives and TPA derivatives-based hole transport materials for perovskite solar cells

Abstract

Developing cost-effective and high-performance hole transport materials (HTMs) is one of the hot topics in the researches of perovskite solar cells (PVSCs). By introducing a carboxyl group on the 3,4-ethylenedioxythiophene (EDOT) derivatives and replacing the –OCH3 (-OMe) groups on the Triphenylamine (TPA) derivatives to -N(CH3)2 groups, we present two efficient strategies for improving the performances of HTMs. The ground-state and excited-state properties, stabilities, solubilities and hole mobility of HTMs are comprehensively studied by DFT and TD-DFT. Both strategies have positive effects on the performance of HTMs. Two designed HTMs C1-R2 (μh = 1.05×10-2cm2 V−1 s−1) and C2-R2 (μh = 1.9×10-3cm2 V−1 s−1) show higher hole mobility than original HTMs C1-R1 (μh = 6.7×10-3cm2 V−1 s−1) and C2-R1 (μh = 1.3×10-3cm2 V−1 s−1) after the replacement on the TPA derivatives, which ensures the fact that these two designed HTMs have potentials in the application of PVSCs. It is hoped that our investigation can provide valuable strategies for conquering the predicament of the application and commercialization of PVSCs.