Tailoring Diversified Peripheral Anchor Groups in Spirofluorene‐Dithiolane‐Based Hole Transporting Materials for Efficient Organic and Perovskite Solar Cells from First‐Principle

Abstract

This quantum mechanical approach recommends push–pull molecular engineering to fabricate hole‐transporting materials (HTMs) for photovoltaic cells. It integrates acceptor moieties via thiophene to fluorene core, resulting in five novel HTMs (SFD‐1 to SFD‐5). The results exhibit that derivative HTMs show excellent coherence in excitation, dispersion, and transportation of charge carriers, ensuring robust hole mobility. The anchor moieties functionalized HTMs unveil excellent band alignment with perovskite with fitting HOMO energy levels (−4.93–−5.35 eV), less optical absorption in visible portion ( < 520). This acceptor integration has improved the hole mobility in derivatives, accredited to the smaller hole reorganization energy (0.14–0.68 eV), and greater hole transfer integral (0.22–0.33 eV). The transition density matrix analysis exhibited robust electronic coupling, subtler charge carrier overlapping and greater charge transfer length (7.48–13.73 Å). This resulted in an excellent upsurge in intrinsic charge transference (70.75–92.70%) and smaller exciton binding energy, leading to easier exciton dissociation, and fewer recombination fatalities. However, an adequate variation in dipole moment (4.04 D to 16.34 D) and Gibbs solvation‐free energy (−18.06 to −21.89 kcal mol−1) ensures facile film formation and processability. In conclusion, this approach recommends these flourene‐based HTMs are highly desireable for forthcoming solar cell technology.