Cs Content‐Dependent Photovoltaic Performance of Cs _<i>x</i> Rb _{1− <i>x</i>} PbI ₃ ‐Based Perovskite Solar Cells

All inorganic perovskite materials consisting of Cs and Rb cations offer an exciting opportunity to fabricate more tunable absorber layers for highly stable solar cell devices. Herein, a 1D solar cell capacitance simulator (SCAPS‐1D) is utilized to comprehensively study the photovoltaic performance of all‐inorganic Cs x Rb 1− x PbI 3 ‐based perovskite solar cells as a function of Cs content ( x ). The input parameters of SCAPS 1D, such as electron and hole mobilities, are evaluated as a function of x for Cs x Rb 1− x PbI 3 . Equations for x‐ dependent photovoltaic parameters are derived. Superstrate n–i–p solar cell processed with architecture of ITO/TiO 2 /Cs x Rb 1− x PbI 3 /P3HT/Au achieves a promising power conversion efficiency of over 11%. Simulations are also carried out to determine device performance by varying interface defects, series, and shunt resistance as a function of x . The device that obtained x = 0.2 of Cs content withstands various rigorous effects of varying interface defects, series, and shunt resistance. The findings presented herein will promote the development of all‐inorganic Cs x Rb 1− x PbI 3 perovskite‐based solar cells.