Growth of Metal Halide Perovskite, from Nanocrystal to Micron-Scale Crystal: A Review

Metal halide perovskite both in the form of nanocrystal and thin films recently emerged as the most promising semiconductor material covering a huge range of potential applications from display technologies to photovoltaics. Colloidal inorganic and organic–inorganic hybrid metal halide perovskite nanocrystals (NCs) have received tremendous attention due to their high photoluminescence quantum yields, while large grain perovskite films possess fewer defects, and a long diffusion length providing high-power conversion efficiency in planar devices. In this review, we summarize the different synthesis routes of metal halide perovskite nanocrystals and the recent methodologies to fabricate high-quality micron scale crystals in the form of films for planar photovoltaics. For the colloidal synthesis of halide perovskite NCs, two methods including ligand-assisted reprecipitation and hot injection are mainly applied, and the doping of metal ions in NCs as well as anion exchange reactions are widely used to tune their optical properties. In addition, recent growth methods and underlying mechanism for high-quality micron size crystals are also investigated, which are summarized as solution-process methods (including the anti-solvent method, solvent vapor annealing technology, Ostwald ripening, additive engineering and geometrically-confined lateral crystal growth) and the physical method (vapor-assisted crystal growth)