Synthesis, Structure, and Optical Properties of Large FAPbBr3 Perovskite Single Crystals

The high power conversion efficiency of perovskite solar cells reaching 25.5% today [1 NREL, Best Research-Cell Efficiency Chart, https://www.nrel.gov/pv/cell-efficiency.html (accessed Feb. 10 2021). [Google Scholar]], raises the question on the relation between the photovoltaic performance and physical nature of these materials. To get a better understanding of the properties, good quality single crystals are highly demanded. In this paper we report on large single crystals of formamidinium lead halide grown by a combination of inverse temperature crystallization and seed growth. Structure, phase transitions, dielectric and optical properties of the single crystals are shown.