Kumar, S.Thiyyakkandy, J.Yadav, A.K.Vinturaj, V.Garg, V.Prabhu, S.Pandey, S.K.2026-02-042024Physica Status Solidi (B): Basic Research, 2024, 261, 9, pp. -3701972https://doi.org/10.1002/pssb.202400247https://idr.nitk.ac.in/handle/123456789/20947The 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 Cs<inf>2</inf>TiBr<inf>6</inf>, which offers a nontoxic alternative. Herein, the electronic and optical characteristics of Cs<inf>2</inf>TiBr<inf>6</inf> absorber material using density functional theory employing the WIEN2K tool are investigated. The energy band structure of Cs<inf>2</inf>TiBr<inf>6</inf> 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 Cs<inf>2</inf>TiBr<inf>6</inf> 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 Cs<inf>2</inf>TiBr<inf>6</inf>-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. © 2024 Wiley-VCH GmbH.Band structureBromine compoundsCesium compoundsConversion efficiencyDensity functional theoryOptical conductivityPerovskite solar cellsAbsorber materialCommercialisationComprehensive modelingDensity-functional-theoryGreen energy technologiesInorganicsLarge-scalesPerformancePhotovoltaicsPower conversion efficienciesPerovskite