Green-Solvent Synthesis for In Situ Growth of Perovskite Phosphors without Ligand Assistance

Cesium-lead halide perovskite nanomaterials have been considered new-generation emitters that can meet the requirements of high photoluminescence efficiency and the high color standard of Rec. 2020. However, their practical application is currently hindered by the challenge of achieving better stability and growth in green solvents. In this study, we propose a green-solvent and ligand-free strategy to achieve highly photoluminescent and stable perovskite phosphors by confining them within mesoporous zeolite. The whole process is green because water is the only solvent. The mesoporous molecular sieve confines the growth of perovskite nanocrystals and passivates the defects of perovskites by H-bonding interactions. The as-synthesized perovskite-mesoporous zeolite phosphors show a high PLQY of 81.5% and good stability against oxygen, water, and heat. Besides, the fabricated white LED devices exhibit a wide color gamut (145% for NTSC and 108% for Rec. 2020) with coordinates of (0.333, 0.334). This green-solvent and zeolite-confined synthesis method offers a promising strategy for developing highly luminescent and stable perovskite materials.