  Metal halide perovskite-based semi-conducting hetero-structures have emerged
as promising electronics for solar cells, light-emitting diodes, detectors, and
photo-catalysts. Perovskites' efficiency, electronic properties and their
long-term stability directly depend on their morphology [1-24]. Therefore, to
manufacture stable and higher efficiency perovskite solar cells and
electronics, it is now crucial to understand their micro-structure evolution.
In this study, we perform molecular dynamics simulations to investigate the
formation of cesium lead bromide perovskite on interfaces. Our simulations
reveal that perovskite crystallizes in a heteroepitaxial manner on widely
employed oxide interfaces. This could introduce the formation of dislocations,
voids and defects in the buried interface, and grain boundaries in the bulk
crystal. From simulations, we find that lattice-matched interfaces could enable
epitaxial ordered growth of perovskites and may prevent defect formation in the
buried interface.
