Double lead-free perovskite solar cell for 19.9% conversion efficiency: A SCAPS-1D based simulation study

It is known that the efficiency of organic–inorganic perovskites has reached beyond 25% in the past few years. Lead toxicity has been one of the main challenges for the commercialization of perovskites as solar cells. Keeping these problems in mind, we used MACa 0.5 Ge 0.5 I 3 (WBG 1 ) and MACa 0.125 Ge 0.875 I 3 (WBG 2 ) to design Pb-free perovskites solar cells. Using these compounds, we have investigated that mixed perovskite can deliver 19.9 % conversion efficiency by performing thickness variation in both WBG 1 and WBG 2 simultaneously.