Submicrocubes and highly oriented assemblies of MnCO 3 synthesized by ultrasound agitation method and their thermal transformation to nanoporous Mn 2O 3

Abstract

MnCO 3 submicrocubes and highly oriented MnCO 3 nanocrystal assemblies with an ellipsoidal morphology have been successfully prepared by an ultrasonic solution approach. The effect of surfactants of sodium dodecylsulfate (SDS) and aerosol OT (AOT) on the morphology of MnCO 3 was investigated. Highly oriented ellipsoidal assemblies composed of ∼5 nm MnCO 3 nanocrystals with porous nanostructures were prepared in the presence of SDS. Both sonochemical irradiation and surfactant play an important role in the formation of these highly oriented assemblies. Nanoporous Mn 2O 3 was obtained by thermal treatment of MnCO 3 at 600 °C in air. The shape of MnCO 3 was sustained after thermal transformation to form nanoporous Mn 2O 3. The products were characterized by X-ray powder diffraction, transmission electron microscopy, selected-area electron diffraction, field emission scanning electron microscopy, thermogravimetric analysis and differential scanning calorimetric analysis.