Single-crystalline Mn_(3)O_(4)nanoflakes were grown on manganese sheets by one-step thermal oxidation process at 360-500℃in ambient atmosphere.The samples were characterized by scanning electron microscope(SEM),X-ray diffraction(XRD),Raman and transmission electron microscope(TEM).The nanoflakes with a size of 15-20 nm in thickness,~60 nm in width,and~210 nm in length are obtained at 360℃for 24 h.A surface diffusion mechanism is proposed to explain the growth of manganese oxide nanostructures via thermal oxidation,which includes two steps:manganese oxide(MnO/Mn_(3)O_(4))layers form firstly,and then Mn_(3)O_(4)nanostructures grow above the upper metal oxide layer to form multi-layered structures,MnO/Mn_(3)O_(4)/Mn_(3)O_(4)-nanoflakes.The nucleation and growth of Mn_(3)O_(4)nanostructures are related to the surface energy and different growth rates along different crystal directions,which are controlled by the diffusion of the metal and gas molecule.
Ming-Long ZhongBin YangCheng-Jun GuoHai-Ping HuangBai-Xiong LiuHui-Ping Liu
