Control of oleylamine to perovskite ratio in synthesis of MAPbBr3 nanoparticles

Methylammonium lead bromide (CH 3 NH 3 PbBr 3 ) nanocrystals have great potentials for lighting and display applications. Previously we synthesized CH 3 NH 3 PbBr 3 nanocrystals using oleylamine as capping molecule and found that by increasing the oleylamine to CH 3 NH 3 PbBr 3 perovskite ratio (OPR), the photoluminescence wavelengths and morphology of CH 3 NH 3 PbBr 3 nanocrystals could be varied from 530 nm (green) platelets to 460 nm (blue) particles. Here we modified the synthesis to direct injection of precursors into toluene and found that increasing OPR not only changes the wavelength and morphology of nanocrystals but also the size of the unit cells.