Impact of Structural Strain on Performance of Halide Perovskite Solar Cells: A Combined DFT and SCAPS‐1D Analysis

The halide perovskites have received extensive experimental and theoretical research interests for photovoltaic application. Most of the theoretical research is based on either material or device modeling approaches. However, literature is still deprived of studies based on the combination of these approaches, which are expected to yield predictions with superior accuracy. This report combines the first‐principles density functional theory (DFT) computations and device modeling to understand the impact of structural strain, generally induced during the crystallization phase of perovskite materials, on the photovoltaic performance of methyl ammonium lead halide (CH3NH3PbI3 or MAPbI3) based solar cell. The magnitude of strain varies in the range from +2% (tensile) to −2% (compressive). The impact of strain is analyzed in terms of the variations in band structure and values of optoelectronic parameters obtained using DFT calculations and further, their impact on performance metrics of solar cells is predicted using device simulations. The optimized cell efficiency under strain‐free conditions is 13% while it deteriorated to 1.6% under +2% tensile strain and improved to 22.3% under compressive strain. The simulation results underline the importance of engineering the structural strain during the crystallization of perovskite absorber material to achieve solar photovoltaic cells of high efficiency. DFT modeling of cubic MAPbI3 perovskite under strain‐free, tensile, and compressive strain. SCAPS modeling of MAPbI3 solar cell under different strain values. Optoelectronic parameters degraded under tensile while improved under compressive strain. The minimum and maximum efficiency is 1.6% and 22.3% under 2% tensile and compressive strain conditions, respectively. Results emphasize the importance of structural engineering in perovskite solar cells.