Size-tunable CsPbBr3 perovskite ring arrays for lasing

Abstract

Morphology engineering is a decisive factor for the optoelectronic properties of nanocrystals. Differing from morphologies with a solid interior, ring-like structures have a unique internal space which is not only available for loading chemicals, but also useful for controlling the field distribution. Herein, the perovskite array family welcomes a new member – CsPbBr₃ ring arrays. This work solves several fundamental problems for fabricating CsPbBr₃ ring arrays: (i) developing a simple method using 2D colloidal crystal templates to achieve ring arrays of CsPbBr₃, (ii) finding two ways, say changing the template size or annealing of the template, to accurately tune the ring size of the array in a wide range from 2.6 μm to 16.9 μm, and (iii) investigating the dynamics of perovskite rings, which indicates a shrinking process towards the template spheres before the crystallization of the perovskites. Finally, the application of CsPbBr₃ perovskite ring arrays to the field of lasers is shown.