Comprehensive Modeling of High‐Performance All‐Inorganic Cs2TiBr6‐Based Perovskite Solar Cells

The perovskites are desirable materials for photovoltaic and other renewable green energy technologies. Lead‐based perovskite solar cells (PSC) have recently gained considerable attention due to the abrupt rise in power conversion efficiency, but lead's well‐known toxicity prevents its large‐scale commercialization. One compelling option is Cs2TiBr6, which offers a nontoxic alternative. Herein, the electronic and optical characteristics of Cs2TiBr6 absorber material using density functional theory employing the WIEN2K tool are investigated. The energy band structure of Cs2TiBr6 shows an indirect bandgap of 2.2 eV. Additionally, optical properties are calculated, and the suitability of this material as an absorber for indoor and outdoor photovoltaic devices is investigated. The Cs2TiBr6 material has a peak absorption coefficient of 39.57 × 104 cm−1 and optical conductivity of 1.98 × 1015s−1, demonstrating its suitability as an absorber material. After that, a PSC is modeled using SCAPS‐1D by using the computed parameters. The performance of the modeled perovskite is enhanced by optimization of various parameters, resulting in the achievement of a high‐performance Cs2TiBr6‐based PSC, boasting a power conversion efficiency of 19.9% for air mass AM1.5 G spectra and power conversion efficiency of 16.76% for light emitting diode and 17.18% for incandescent light for indoor light conditions.