High Green Purity and Narrow Emission Ceramic-Like Perovskite Nanocrystals Enabled by Solid-Phase Reaction Process

Here, ceramic-like CsPbBr3@SiO2 nanocrystals (NCs) with a high photoluminescence quantum yield of 98.7%, green purity of 90%, and narrow full width at half maximum of 22 nm are successfully achieved by a solid-phase reaction process. The SiO2 shell covers the surface of the NCs, providing long-term working and excellent thermal cycling stability. Ba2+ dopes the lattice of the perovskite structure under high-temperature sintering at 700 degrees C, resulting in the red-shift of the NCs emission due to the decrease of the bandgap caused by the lattice modulation with Ba2+. At the same time, the halogen vacancies are effectively passivated by a halogen-rich environment of dopants (BaBr2). The Commission Internationale de l'Eclairage of the doped ceramic-like NCs is (0.170, 0.760), which approaches the Rec.2020 standard. By means of this solid reaction process, red, green, and blue ceramic-like perovskite NCs are prepared to achieve white light-emitting diodes, covering 124% of the National Television Standards Committee.