Temperature-Dependent Performance of FTO/SnO₂/CsPbI₂Br/CsSnI₃/CuI/Au Dual-Absorber Perovskite Solar Cells: A SCAPS-1D Study

Abstract

Perovskite solar cells have attracted significant attention because of their strong optical absorption, tuneable band gaps and favorable carrier-transport properties; however, their photovoltaic performance is strongly influenced by operating temperature. Understanding thermal sensitivity is therefore important for improving device stability and performance. In this study, the temperature-dependent photovoltaic behaviour of an FTO/SnO₂/CsPbI₂Br/CsSnI₃/CuI/Au dual-absorber perovskite solar cell was investigated using SCAPS-1D version 3.3.12. The device was simulated from 300 to 400 K at 10 K intervals under AM1.5G illumination with an incident power density of 100 mW cm⁻². The effects of temperature on open-circuit voltage (Voc), short-circuit current density (Jsc), fill factor (FF), power conversion efficiency (PCE), maximum-power voltage (V_MPP) and maximum-power current density (J_MPP) were evaluated, together with temperature-dependent carrier redistribution and recombination behaviour. At 300 K, the device exhibited Voc = 0.9781 V, Jsc = 26.2441 mA cm⁻², FF = 82.93%, PCE = 21.29%, V_MPP = 0.8400 V and J_MPP = 25.3427 mA cm⁻². With increasing temperature, Voc decreased to 0.8345 V at 400 K, whereas Jsc remained nearly constant at 26.24 mA cm⁻². FF reached a maximum of 83.76% at 340 K before declining to 81.61% at 400 K, while PCE decreased to 17.87%. Regression analysis of the simulated data yielded linear temperature coefficients of −1.437 mV K⁻¹ for Voc, −1.88 × 10⁻⁶ mA cm⁻² K⁻¹ for Jsc, −0.0155 percentage points K⁻¹ for FF, and −0.0348 percentage points K⁻¹ for PCE. The results show that performance degradation at elevated temperatures is driven primarily by voltage and efficiency losses rather than photocurrent reduction, accompanied by carrier redistribution, modified spatial recombination profiles, and internal electric-field variation.