Cs4PbBr6/CsPbBr3 Nanocomposites for All-Inorganic Electroluminescent Perovskite Light-Emitting Diodes

In this study, the facile synthesis and electroluminescent perovskite light-emitting diodes (PeLEDs) of highly luminescent Cs 4 PbBr 6 /CsPbBr 3 nanocomposite has been demonstrated. With the addition of proper antisolvents, the nanocomposite with a production yield of >90% and quantum yield of >85% was readily derived from the transformation of CsPbBr 3 powder. The obtained high quantum yield of the green nanocomposite originated from the fluorescent CsPbBr 3 nanocrystals embedded in the Cs 4 PbBr 6 matrix, which was verified by X-ray diffraction, absorption, photoluminescence (PL), and PL excitation spectra. The addition of large cation precursors, such as CsBr and CH(NH 2 ) 2 Br, could contribute to the transformation efficiency and had no influence on the composition of the embedded nanocrystals. Via the thermal evaporation of the nanocomposite, all-inorganic electroluminescent PeLEDs with CuSCN and Cu-doped NiO x (NiO x:Cu) nanoparticles were fabricated and characterized. A maximum luminance of 1780 cd/m 2 and efficiency of 0.43 cd/A were achieved. Thus, the luminescent Cs 4 PbBr 6 /CsPbBr 3 nanocomposite is a promising material for next-generation displays and lighting.