Synthesis and Improved Photoluminescent Properties and Stability of Bromine‐Rich CsPbBr3 Nanocrystals Via using CTAB as Additive

Abstract Although CsPbBr 3 nanocrystals (NCs) show excellent optoelectronic properties, their stability greatly limits their potential applications due to the ionicity. Stable bromine‐rich CsPbBr 3 nanocrystals (NCs) are achieved by the thermal injection method, which includes adding cetyltrimethylammonium bromide (CTAB) to a cesium oleate precursor solution. The CTAB as a ligand provides strong binding to the NC surface to effectively passivate the surface defects, and most importantly helps to realize the formation of bromine‐rich CsPbBr 3 NCs. The obtained bromine‐rich CsPbBr 3 NCs show higher photoluminescence quantum yields (PLQYs) and enhanced moisture and UV illumination stability. These results provide a simple strategy to synthesize bromine‐rich CsPbBr 3 NCs, which can be promising for integrating into the synthesize technique of perovskite optoelectronic devices.