Tailoring the D‐A‐D electron‐withdrawing core as hole transport materials towards boosting the transport performance of perovskite solar cells

Abstract Five donor‐acceptor‐donor (D‐A‐D) hole transport materials (HTMs) are investigated to reveal the effect of core units on the structure‐property relationship. Structurally, the five electron‐withdrawing cores are derivatives of diazosulfide, and the bis(N, N‐bis(4‐[methoxy]phenyl))aniline segment performed as the symmetrical end‐capping. The DFT and TD‐DFT coupled with the Marcus theory are used to look into electronic structures, ground and excited state properties, charge transport mobilities, and charge transfer analyses. It is found that the HTM‐PT shows little differences in planarity, ionization potential, and solubility compared with the original molecule. Additionally, the HTM‐PT exhibits lower frontier molecular orbital (FMOs), smaller bandgap, and red‐shift than HTM‐DP. More importantly, among the four designed HTMs, the HTM‐PT shows a larger hopping rate and mobility. As the charge transfer analyses, the HTM‐PT exhibits a larger intramolecular charger transfer amount and charge transfer distance than the prototypical one, which is conducive to a larger short‐circuit current. Through the evaluation from various aspects, it is reasonable to infer that PT‐core with excellent properties has potential advantages in regulating HTMs.