Morphologically stable and controlled shape of CsPbBr₃perovskite nanoparticle synthesized at room temperature with curing time

All-inorganic perovskite CsPbBr3 nanoparticles (NPs) have gained tremendous attention because of their versatile potential application in optoelectronics, sensor, and energy storage devices. However, poor stability is a bottleneck for its implementation in device fabrication. This study focused on improving stability and controlling the shape of CsPbBr3 NPs synthesized at room temperature with curing time. The CsPbBr3 NPs were prepared by ligand assisted re-precipitation (LARP) using CsBr and PbBr2 as precursor materials. The as-prepared CsPbBr3 NPs were cured for 12, 24, and 48 hours. The effect of curing time on the shape and stability of NPs in humidity and organic solvents (methanol, ethanol, and dichlorobenzene) was studied. TEM and SAED analysis show that a perfect cubic shape of CsPbBr3 NPs obtained after 48 hours curing. XRD and DLS measurement indicate the NPs underwent 48 hours curing have excellent morphological stability. No significant changes in crystal pattern and particle size were observed after dispersion in organic solvents. Nevertheless, the CsPbBr3 NPs cured in less than 48 hours provide random-shaped particles and degrade morphologically in the presence of humidity and organic solvents. The results demonstrate a promising preparation method of stable CsPbBr3 NPs at room temperature that suitable for device fabrication.