Highly Stable CsPbI3 Perovskite Quantum Dots Enabled by Single SiO2 Coating toward Down-Conversion Light-Emitting Diodes

All-inorganic CsPbI3 perovskite quantum dots (PeQDs) have sparked widespread research due to their excellent optoelectronic properties and facile synthesis. However, attaining highly stable against heat polar solvents still remains a challenge hinders any further practical application. Here, by exploiting (3-aminopropyl) triethoxysilane (APTES) as the sole silica (SiO2) precursor, we report one-step in situ synthesis of single SiO2-coated (SiO2-CsPbI3) PeQDs, namely that one SiO2 particle only contains PeQD particle. The obtained SiO2-CsPbI3 PeQDs are cubic shape, more uniform size distribution, possess narrow emission, with near unit photoluminescence yields up 97.5%. Fourier transform infrared spectroscopy X-ray photoelectron confirm formation through hydrolysis APTES on surface. Furthermore, they significantly improved stability storage, heat, ethanol. By combining purple-emission GaN light-emitting diodes, were successfully employed down-conversion emitters exhibited considerable enhanced luminous performance stability, demonstrating promising future application solid-state lighting fields.