Harnessing the potential of lead-free BiFeO₃-based perovskite solar cell architectures: a gateway to next-generation...

An inorganic, lead-free n-i-p structured perovskite solar cell based on BiFeO₃ (BFO) is employed and optimized using 3D COMSOL Multiphysics simulations to address the urgent shift from fossil fuels to renewable energy driven by environmental challenges. The solar cell structure incorporates ZnSe as the electron transport layer, BFO as the perovskite absorber layer, and Spiro-OMeTAD as the hole transport layer. A detailed analysis is conducted to evaluate the effect of layer thicknesses, perovskite layer, electron transport layer, hole transport layer, relative permittivity, electron mobility, donor density, acceptor density, series, shunt, characteristic resistances, carrier lifetime, and electron-hole recombination on device performance. The optimized design achieves a remarkable power conversion efficiency of 10.866% with an open-circuit voltage of 2.32 V, a short-circuit current density of 7.25 mA cm^-2, a power maximum of 108.66 W m^-2, and a fill factor of 64.47% at an optimal ETL relative permittivity of 4. The adoption of lead-free materials enhances environmental safety, operational stability, and device longevity. This study highlights the potential of BFO-based perovskite solar cells to drive sustainable photovoltaic innovations, with promising applications in portable electronics, building-integrated photovoltaics, and scalable renewable energy systems.