A molecular engineering approach was employed to design furan (Fu-2a, Fu-2b, Fu-2c) and quinacridone (Dm-Q)-based organic hole-transporting materials (HTMs) with the objective of improving the charge transfer properties and overall performance of perovskite solar cells (PSCs). The alignment of the frontier energy levels in the designed HTMs was carefully optimized, facilitating efficient hole injection at the perovskite/HTM interface while effectively suppressing electron-hole recombination and preventing undesired electron extraction. The studied materials demonstrated a pronounced preference for hole transfer over electron transfer based on their physical characteristics. Importantly, Fu-2b and Fu-2c exhibited red-shifted absorption spectra due to the incorporation of a -C6H4-C6H4- chain, resulting in a narrower bandgap energy. A detailed analysis of the dimer charge transfer properties, including intermolecular distances, charge carrier electronic coupling, hopping rates, and mobility, further underscored the superior suitability of these materials for hole injection compared to electron injection. Among the investigated HTMs, Fu-2a was identified as the most promising candidate, exhibiting the lowest electron affinity (0.61 eV), highest light-harvesting efficiency (0.93), oscillator strength (1.19), and exceptional hole transfer properties, including electronic coupling (83 meV), hopping rate (1.90 × 1012 s−1), and mobility (0.81 cm2 V−1·s−1).

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