CsPbBr3

CsPbBr3 is an inorganic lead bromide perovskite with the formula CsPbBr3. In ABX3 perovskites, Cs+ occupies the A site, Pb2+ the B site, and Br− the X site, forming a three-dimensional network of corner-sharing PbBr6 octahedra. At room temperature it is orthorhombic, with phase transitions to tetragonal and cubic phases at higher temperatures.

CsPbBr3 has a direct bandgap around 2.3 eV, resulting in strong visible absorption and green emission near 520–535 nm, depending on crystallinity and size. In nanocrystal form, CsPbBr3 often shows high photoluminescence quantum yields and narrow emission spectra.

Bulk crystals, thin films, and colloidal nanocrystals can be synthesized. Common solution routes include hot-injection and ligand-assisted reprecipitation from CsBr and PbBr2 in coordinating solvents, with surface ligands such as oleylamine and oleic acid stabilizing nanocrystals and influencing stability and optoelectronic properties.

Applications are concentrated in optoelectronics, especially light-emitting diodes and photodetectors; CsPbBr3 nanocrystals are used for green emitters in LEDs and display technologies. While studied for solar cells, perovskite solar devices based on CsPbBr3 are less developed than lead–iodide counterparts.

Stability remains a challenge due to moisture, heat, and chemical degradation. Lead content raises environmental and safety concerns, prompting research into encapsulation, surface engineering, and substitutions to improve durability and reduce toxicity.