Structure Evolution of CH₃NH₃PbBr₃ Single Crystal Grown in <i>N</i>,<i>N</i>‑Dimethylformamide Solution

CH₃NH₃PbBr₃ single crystal, one of organometal halide perovskites, as novel optoelectronic and photovoltaic materials could be easily precipitated using an antisolvent method. Understanding of the growth mechanism will significantly improve reproducibility, quality, and controllability of the single crystals. However, it is difficult to capture the growth process due to the super solubility of CH₃NH₃PbBr₃ crystals in <i>N</i>,<i>N</i>-dimethylformamide solution. Here, filter paper was used to separate the intermediate states of CH₃NH₃PbBr₃ crystals out of <i>N</i>,<i>N</i>-dimethylformamide solution in the growth process. The developed fabrication approach can monitor the morphology evolution of CH₃NH₃PbBr₃ single crystals as a whole. Meanwhile, the precursor solution’s properties and degradation of CH₃NH₃PbBr₃ single crystals were also investigated systematically. It indicates that the CH₃NH₃PbBr₃ single crystal growth process is similar to sodium chloride crystals grown from solution in the presence of nitrilotriacetamide. The results help us to deeply discern the growth mechanism of CH₃NH₃PbBr₃ single crystal in <i>N</i>,<i>N</i>-dimethylformamide solution and design controllable optoelectronic devices