Formation of bright-green-color-emitting perovskite CsPbBr3 in a bulk state using a simple recrystallization process

Abstract

A highly luminescent CsPbBr3-perovskite structure was synthesized by dropping a PbBr2-DMF solution to bulk CsBr. The bulk CsBr was used as the matrix for the CsPbBr3. The product showed a strong green emission with a narrow full width at half maximum (FWHM). This method is very fast, and it is suitable for mass production and large-area coating. The particle sizes are more than hundreds of nanometers, and orthorhombic crystal structures are also evident. Interestingly, the case here shows a strong photoluminescence (PL) emission at room temperature (RT). A new hypothesis between the particle size of CsPbBr3 and the quantum yield (QY) is therefore suggested by the authors. The free charge carriers in the bigger particles have enough space for free migration, and as a result, the probability of recombination is decreased and a low QY is observed. The migration of the free charge carriers in small particles is inhibited by a spatial limit. The CsPbBr3 particles can be directly synthesized on diverse substrates including glass, fabric, and paper. The finding of this study can provide a novel way to achieve applications and scalable processes; especially, owing to the substrate diversity, it can be applied to continuous processes such as R2R for mass production.