Optimization of lead-free BiFeO3 perovskite solar cell for efficient solar potential in futuristic green technologies

Abstract

The adverse effects of global warming and dependence on hazardous energy sources like coal and petroleum have shifted focus toward solar energy, a sustainable and clean solution. Perovskite materials, particularly BiFeO3, are attracting attention as absorber layers due to their multifunctional properties. This study employs COMSOL to simulate 1D TiO2/BiFeO3/Spiro-OMeTAD solar cell with ideal ohmic contacts at different operating temperatures. The results demonstrate that short-circuit current density increases with BiFeO3 thickness, and efficiency peaks at an optimal thickness. However, the maximum efficiency of 10.88% is achieved (in TiO2/BiFeO3/Spiro-OMeTAD) when the electron transport layer has density of states in valence and conduction band (NCNV) ~ 2×1016 cm-3 while TiO2/SnS/BiFeO3/Spiro-OMeTAD showed maximum efficiency of 20.99% at 700 nm thickness of SnS layer. Moreover, an increase in BiFeO3’s bandgap enhances the open-circuit voltage (Voc) but reduces the fill factor. On the other hand, the BiFeO3’s NCNV has no significant impact on efficiency but shows inverse coupling with Voc. Additionally, increasing BiFeO3’s electron affinity improves the fill factor, while TiO2’s electron affinity enhances Voc, and that of Spiro improves power output. This work provides insights for optimizing material properties and device parameters in experimental applications and highlights the potential of BiFeO3-based perovskite for next-generation photovoltaics.