Role of Aromatic Heterocyclic Core-Based Materials as Donors for Organic and as Hole-Transporting Materials for Perovskites Solar cells

Abstract

Hole-transporting materials (HTMs) have revolutionized the field of photovoltaics for solar cell devices. Herein, novel butterfly-shaped hole transport material (HTM) 2,7-DMPZ (R) containing twisted core unit is used to develop novel molecules (Q1–Q6) by fitting suitable donor groups at peripheral regions of 2,7-DMPZ. To investigate the power conversion efficiency (PCE) of Q1–Q6, different analyses, including optical, frontier molecular orbitals (FMOs), molecular electrostatic potential (MEP), density of states (DOS), transition density of states (TDM), and charge transfer (CT) analysis are employed using various density functional theory (DFT) and time-dependent-DFT (TD-DFT) approaches. Excitation, binding, and reorganization energy along with open-circuit voltage of Q1–Q6 molecules are estimated. The UV–Visible study elucidates that these molecules exhibited redshifts (329–343[Formula: see text]nm) absorption higher and comparable with the R molecule (342[Formula: see text]nm). The HOMO–LUMO gap of Q1–Q6 (5.31–5.38[Formula: see text]eV) is also narrower than R (5.49[Formula: see text]eV), indicating that designed molecules can show higher charge transfer than R, which can ultimately produce higher PCE values. In case of hole reorganization energy, the hole mobilities are found more valuable than R. For charge transfer analysis, the Q6 molecule is complexed with PC[Formula: see text]BM acceptor polymer that shows promising charge transfer between the Q6/PC[Formula: see text]BM complex. All studies illustrate that proposed molecules (Q1–Q6) have a great capacity to further improve the optical and photovoltaic parameters when they will be used in efficient organic (as donors) and perovskite (as HTM) solar cells and can show higher performances than R. Therefore, these newly designed molecules (Q1–Q6) rerecommended to the experimentalists for the synthesis to be employed as donors in organic and as HTMs in perovskite solar cells applications.