Bifunctional Central Acceptor Engineering of Tetrathiafulvalene‐Based Dopant‐Free Hole Transport Materials for Perovskite Solar Cells: Density Functional Theory/Time‐Dependent Density Functional Theory Investigation

Perovskite solar cells (PSCs) require dopant‐free hole transport materials (HTMs) to enable low‐cost, stable device architectures. This study introduces a bifunctional central acceptor engineering strategy on a tetrathiafulvalene (TTF) donor scaffold, in which five HTM candidates (BA1–BA5) were designed from the reference molecule BAR via central acceptor modification. A theoretical evaluation was performed at the B3LYP/6‐31G(d,p) level to assess their potential as HTMs for PSCs. The designed molecules exhibit strong optical absorption in the 812–1115 nm range in dichloromethane with higher oscillator strengths than BAR. The highest occupied molecular orbital–lowest unoccupied molecular orbital (LUMO) gap narrows from 3.18 eV in BAR to 1.29–1.82 eV in BA1–BA5, driven by LUMO stabilization, and decreased reorganization energies indicate more favorable charge transfer characteristics. BA3 shows low hole and electron reorganization energies; its ground‐state dipole moment increases up to 2.6‐fold, indicating enhanced molecular polarity and a stronger response to the solvent environment. Open‐circuit voltages estimated against the PC ₆₁ BM reference acceptor range from 0.63 to 0.86 V. Among the series, BA2 and BA3 emerge as the promising candidates, combining favorable energy‐level alignment, excited‐state characteristics, and molecular‐level charge transfer indicators. These computational results establish central acceptor engineering as an effective strategy for tuning TTF‐based dopant‐free HTMs, and identify molecular targets for synthesis and device‐level validation.