Controlled synthesis of monodisperse manganese oxide nanocrystals

Abstract

Monodisperse manganese oxide nanocrystals (NCs) have been successfully synthesized through the decomposition of Mn(acac)₂ in nonpolar solvent. By simply adjusting the nucleation temperature, NCs with Mn₃O₄ or MnO structures were synthesized in sizes ranging from 5 to 25 nm. To obtain monodisperse NCs, the growth temperature was set at 30 °C lower than the nucleation temperature by injecting paraffin oil. It has been demonstrated that every ligand (including oleic acid, oleylamine, and dodecanol) played an important role during the synthesis process. The structure and shape properties of manganese oxide NCs synthesized with different ligands have been studied and characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and transmission electron microscopy (TEM).