Facile production of CsPbBr3 perovskite single-crystals in a hydrobromic solution

Abstract

In this study, synthesis of CsPbBr3 perovskite single-crystals in a hydrobromic solution was investigated. Single-crystal growth experiments were conducted at the solution-nucleation border at a constant temperature or controlled cooling conditions. Working at the solution-nucleation border poses some practical difficulties such as fast precipitation. Often researchers opt to oversaturate the solution and use the supernatant after filtration. However, for conditions where the A to B ratio in the precursor solution for the formation of ABX3 is not 1, oversaturation is a waste of resources. In this work, precursor solutions were prepared for a particular working temperature and either held at a constant temperature or were gradually cooled to a predetermined temperature. The constant temperature method resulted in large and clear crystals as it reached saturation more slowly. Crystals prepared at high temperatures appeared to be more transparent with clear facets. Crystals prepared at low temperatures appeared to be opaque with multiple nuclei growth on a single-crystal. Seeding of the saturated solution resulted in larger single-crystals. The procedure adapted in this work made possible the production of clear CsPbBr3 perovskite single-crystals in a hydrobromic acid solution with sizes of up to 5 mm in only 10 days.