Figure 1.

Nonclassical recrystallization. First, the “impure” colloidal agglomerate is redispersed in solvent and afterward recrystallized to mesocrystals. The recrystallization step tends to exclude “colloidal impurities”. The crystallization of mesocrystals is reversible. Therefore, “colloidal impurities” can be removed by repeated recrystallization, separating the supernatant from the mesocrystals. This process accumulates nanocrystals of higher quality within the mesocrystals, which can be again redispersed in any solvent.