Development of cost-effective diphenylamine substituted hole transporting materials for organic and perovskite solar cells

Abstract

In recent years, material developments have continued to increase the performances of organic and perovskite solar cells (PSCs). Therefore, herein, we designed (HRN1-HRN11) and characterized eleven new hole transport materials (HTM) for PSCs. A systematic investigation has been conducted to investigate the optoelectrical characteristics of these HTMs. The optical characteristics and structure of these modeled HTMs have been analyzed using density functional theory (DFT) and time-dependent (TD-DFT). Ionization potential, electron density difference (EDD), electron and hole reorganizational energies, charge transfer analysis, transition density matrix, and molecular electrostatic potential analysis were performed to investigate the potential of these designed series (HRN1-HRN11) for PSCs. In comparison to the synthetic reference molecule (HRN), which has a band gap of 3.64 eV and a wavelength of 388.69 nm, the newly developed compounds (HRN1-HRN11) show promising optoelectronic qualities with much lower energy gaps (up to 2.01 eV) and absorbed maximum absorption wavelength (940.99 nm). Together with their excellent hole and electron transport capabilities, improved open-circuit voltage values of 1.06–1.34 eV are calculated. The acceptor and donor regions of HRN2, HRN7, and HRN1 exhibit great charge mobility and have the lowest electron reorganization energy. HRN9 has the greatest reorganization energy of hole (λ_h) value among all designed molecules. The work emphasizes designing suitable photovoltaic materials to produce highly efficient solar cell devices.