Development and Modeling of Lead‐Free Perovskite Heterojunction Solar Cells Incorporating MASnI 3 and Rubidium‐Based Halides
Khadeeja Mumtaz, Muhammad Farooq Nasir, Muhammad Imran Malik, Irfan Qasim, Sikander AzamABSTRACT
An efficient solar cell design that does not use lead was created using a multiabsorber heterojunction structure comprising MASnI 3 , RbSnCl 3 , and RbGeI 3 layers. SCAPS‐1D simulations of the device configuration FTO/CdZnS/MASnI 3 /RbSnCl 3 /RbGeI 3 /CuO/Au attained a significant power conversion efficiency (PCE) of 25.56%, with a short‐circuit current density ( J sc ) of 35.12 mA/cm 2 , an open‐circuit voltage ( V oc ) of 0.99 V, and a fill factor (FF) of 73.41%. The simulation results show the impact of absorber layer thickness, interface defect concentrations, dielectric permittivity, and thermal conditions on device efficiency. Remarkable quantum efficiency, over 98% in the visible spectrum, indicates exceptional charge creation and collection. Shockley–Read–Hall (SRH) recombination was identified as the primary performance‐limiting mechanism, especially at the CuO/perovskite interface. Strategic interface and band alignment engineering markedly diminished recombination losses, validating the potential of lead‐free, entirely inorganic perovskite materials for future solar solutions that are both high‐performing and environmentally friendly.