Ligand-Controlled Formation and Photoluminescence Properties of CH3NH3PbBr3 Nanocubes and Nanowires

Light-emitting halide perovskites are currently emerging as promising solution-processed materials for optoelectronic applications, and correlations between their physical properties and morphologies are important drivers to guide material and device optimization. There is still a lack of precise control of the morphology in colloidal perovskite materials, and in the related studies of their shapedependent optical properties. Capitalizing on our previous works on the ligand-assisted reprecipitation synthesis of colloidal perovskite nanocrystals, we have addressed the role of key experimental parameters in determining the degree of supersaturation that drives the crystallization of CH3NH3PbBr3 precursors. By adjusting the amount of ligands, we fabricated single crystalline CH3NH3PbBr3 nanocubes (size: approximate to 500 nm) and nanowires (length: 2-4.5 mu m, width: approximate to 100 nm), and conducted steady-state, time-resolved, excitation power and temperature-dependent photoluminescence measurements to investigate their shape-dependent photoluminescence properties.