ABSTRACT Previous literature had established that lead‐free perovskite solar cells are a good candidate to replace lead‐based solar cells. However, its low power conversion efficiencies and stability issues become the main drawbacks. There is a need to examine scientific possibilities to optimize its internal mechanism to overcome its inherent drawbacks. This study is a theoretical simulation of the cesium tin‐based double perovskite in a multiple ETLs architecture (specifically, p–n architecture) with the use of …