Controllable Synthesis of Monodisperse Metal Oxide Nanostructures via a Solvothermal Route and Their Catalytic Properties

Abstract

The monodisperse Mn 2 O 3 nanooctahedron, Mn 3 O 4 nanorices, NiO nanoflowers and Cu 2 O nanoroses have been synthesized via a facile solvothermal approach in the presence of poly (vinyl-pyrrolidone)/stearic acid (PVP/SA) as capping agent. Field-emission scanning electron microscopes (FESEM) and X-ray powder diffraction (XRD) were employed to detect the prepared products. Furthermore, the synthetic method appears to be a general approach and other metal oxide materials with various well-defined nano/microstructures can be fabricated by the similar method. The as-obtained metal oxides nanostructures were used as catalyst in CO oxidation, and the octahedral Mn 2 O 3 nanoparticles exhibited relatively high activity. Complete conversion CO to CO 2 can be achieved at a temperature as low as 240 °C over Mn 2 O 3 catalyst, which was about 70 and 100 °C lower than that of Mn 3 O 4 and NiO, respectively.