Preparation and Characterization of MgO nanorods coated with SnO2

초록

MgO-core/SnO2-shell one-dimensional (1D) nanostructures were synthesized by a two-step process: thermal evaporation of MgN powders and atomic layer deposition of SnO2. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis results show that the MgO cores are of a single crystal nature with a cubic structure while the SnO2 shells are amorphous. Scanning electron microscopy reveals that the nanostructures consist of MgO nanorod cores with an average diameter of 150- 200 nm and SnO2 shells with a high thickness uniformity. A blue emission band centered around 440 nm is observed in the room temperature photoluminescence (PL) spectrum of the SnO2-sheathed MgO naorods. The PL emission is not nearly increased in intensity by annealing in an oxidative atmosphere. On the other hand, PL emission is significantly increased and the emission peak is shifted from ~ 440 to ~ 620 nm by annealing in a reducing atmosphere. The origin of the enhancement and shift of the PL emission by annealing in the reducing atmosphere is also discussed based on the energy-dispersive X-ray (EDX) line scanning analysis results.