Room-temperature synthesis of CsPbBr3 and CsPb(Br/Cl)3 with narrow FWHM and high fluorescence intensity

Inorganic perovskite quantum dots (IPQDs) have a series of advantages such as high photoluminescence quantum yield (PLQY), narrow full width at half maximum (FWHM), wide color gamut, and adjustable fluorescence wavelength. In this study, we proposed a facile method to synthesize CsPbBr3 and CsPb(Br/Cl)3 QDs with excellent stability. The IPQD surfaces were modified by chains of EHDAB at room temperature. The obtained CsPbBr3 QDs show cubic shapes with average particle size of about 10 nm. The EHDAB can greatly enhance the PL intensity of IPQDs, and the PL intensity of the solution added to EHDAB was increased by 300% compared with the blank group (without EHDAB). The modified CsPbBr3 QDs can still retain 93.4% of PL intensity after being stored for 12 days at room temperature (25 ℃). The CsPb(Br/Cl)3 quantum dots possessing narrow FWHM of 18 nm were simply obtained by ion exchange at room temperature. The emission wavelength of CsPb(Br/Cl)3 quantum dots could be adjusted from 517 to 456 nm. The results show that the modified IPQDs could be used as potential luminescent materials for optoelectronic devices.