Facile Synthesis of Large Bulk Crystal Based on Perovskite‐Quantum Dots Hybrid Structure

Abstract In this study, the fabrication of a large bulk crystal based on the hybrid structure of CH 3 NH 3 PbBr 3 (MAPBr) and PbS quantum dots (QDs) with excellent crystal lattice match using an in situ epitaxial crystallization technique is presented. The hybrid bulk crystal is successfully constructed by uniformly dispersing PbS QDs within the MAPBr matrix. The crystalline growth method is also changed to achieve the desired hybrid structure. The light emission range is modulated and the light emission lifetime is prolonged by constructing a MAPBr‐PbS hybrid structure. Additionally, the hybrid bulk crystal exhibited an up‐conversion effect, which does not appear in MAPBr single crystal. These findings highlight the promising potential of the MAPBr‐PbS QDs hybrid bulk crystal in the fields of optics and photoelectronic, such as all solid‐state lasers, bio‐imaging, optical data storage, and photovoltaic applications. This in situ hybrid crystallization technique also provides a universal pathway for the preparation of other bulk crystals based on perovskite‐QDs hybrid structures.