Solar Cells: Oriented Grains with Preferred Low‐Angle Grain Boundaries in Halide Perovskite Films by Pressure‐Induced Crystallization (Adv. Energy Mater. 10/2018)

In article number 1702369, Hyunjung Shin, Dongho Kim, Jong Hyeok Park and co-workers report a mechanical crystallization methodology for preferred-orientation and close-packed grains of perovskite materials with uniaxial compression. Simply pressing polyurethane stamps with hexagonal nanodot arrays on partially dried perovskite intermediate films can cause pressure-induced perovskite crystallization, leading to preferred-orientation and enlarged grains with low-angle grain boundaries in the perovskite films. The photovoltaic response dramatically improves in both inverted-planar perovskite solar cells and normal perovskite solar cells, leading to a power conversion efficiency of 19.16%.