High-quality bulk hybrid perovskite single crystals within minutes by inverse temperature crystallization

Abstract

Single crystals of methylammonium lead trihalide perovskites (MAPbX₃; MA=CH₃NH₃⁺, X=Br⁻ or I⁻) have shown remarkably low trap density and charge transport properties; however, growth of such high-quality semiconductors is a time-consuming process. Here we present a rapid crystal growth process to obtain MAPbX₃ single crystals, an order of magnitude faster than previous reports. The process is based on our observation of the substantial decrease of MAPbX₃ solubility, in certain solvents, at elevated temperatures. The crystals can be both size- and shape-controlled by manipulating the different crystallization parameters. Despite the rapidity of the method, the grown crystals exhibit transport properties and trap densities comparable to the highest quality MAPbX₃ reported to date. The phenomenon of inverse or retrograde solubility and its correlated inverse temperature crystallization strategy present a major step forward for advancing the field on perovskite crystallization.