Highly Stable CsPbX3/PbSO4 Core/Shell Nanocrystals Synthesized by a Simple Post-Treatment Strategy

All-inorganic lead halide perovskite (CsPbX3, X = Cl, Br, I, or their mixture) nanocrystals (NCs) have recently emerged as a promising photoelectric material; however, developing highly stable CsPbX3 NCs still remains a challenge due to their intrinsic ionic nature. This work presents a simple and facile post-treatment strategy to encapsulate CsPbX3 NC with PbSO4 nanoshell at single-particle level. Compared to pristine CsPbX3 NCs, the as-prepared CsPbX3/PbSO4 NCs exhibit significant enhancement in the optical properties. Benefiting from the efficient protection of inert PbSO4 nanoshell, the obtained CsPbX3/PbSO4 core/shell NCs demonstrate great stability against polar solvents, including ethanol and acetone, and light irradiation. Furthermore, anion-exchange reaction is strongly restricted upon the encapsulation of PbSO4 shell. This work provides an alternative approach for the synthesis of highly stable CsPbX3 NCs, and paves a new way for the preparation of core/shell heterostructures based on lead halide perovskite NCs.

Automated summary

This study presents a simple and effective post-treatment strategy to encapsulate CsPbX3 NC with PbSO4 nanoshell, significantly enhancing optical properties and demonstrating good stability.