Controlling the Morphology of CH3NH3PbBr3 Perovskite Films on Planar Substrates
AbstractHybrid organic-inorganic metal halide perovskites have recently emerged as one of the most promising new materials for photovoltaics, reaching efficiencies up to 20.1% over a period of only five years. However, for the planar heterojunction device architecture - likely the most commercially scalable design for perovskite solar cells – controlling film morphology remains a significant challenge, inhibiting both device performance and the investigation of fundamental material properties. In this study, surface silane-functionalization of planar substrates was employed together with the addition of hydrobromic acid to the perovskite precursor solution to improve perovskite film uniformity with controlled crystal size and reduced surface roughness.
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