Compositions and Methods for Stabilizing Perovskite Interfaces

The present disclosure relates to a composition that includes a first layer that includes a perovskite defined by ABX.sub.3 and a second layer that includes a perovskite-like material defined by at least one of A'.sub.2B'X'.sub.4, A'.sub.3B'.sub.2X'.sub.9, A'B'X'.sub.4, A'.sub.2B'X'.sub.6, and/or A'.sub.2AB'.sub.2X'.sub.7, where the first layer is adjacent to the second layer, A is a first cation, B is a second cation, X is a first anion, A' is a third cation, B' is a fourth cation, X' is a second anion, and A' is different than A.