Tunable Emission from Organolead Bromide Perovskite Quantum Dots for White Light-Emitting Diodes*

Perovskites are very promising materials for use in optoelectronic devices due to their ability to tune through the visible colors with high quantum efficiency. Chloride based perovskites are most often used to get blue emission. However, working with Chlorine is unnecessarily difficult. To date, there is no significant literature discussing an effective method of obtaining blue emission from Organolead bromide perovskite (MAPbBr₃, MA-CH₃NH₃) quantum dots via increasing the total amount of ligands used. This would make the use of Chlorine unnecessary. Ligand variation has the effect of controlling the crystal growth to a greater degree than previous works have, allowing for very specifically changing the band gap from the standard green to the mid-violet range. Here we demonstrate the Bromide-based quantum dot’s tunability throughout the violet-green color range with high color purity and narrow line-width emission. This narrow emission is accomplished by a facile solution process for MAPbBr₃ quantum dots via changing the amount of ligands used in a room temperature synthesis.