Morphology and photoluminescence of Zn/ZnO core-shell structures by water-boiling method

摘要

Zn/ZnO core-shell structures were synthesized by water-boiling method using induction cooker and electric cooker. The synthesized Zn/ZnO core-shell structures were characterized with X-ray diffraction (XRD), scanning electronic microscopy (SEM) and photoluminescence (PL) spectrophotometer, respectively. The XRD pattern confirms that the shells of the Zn/ZnO core-shell structures are composed of wurtzite ZnO crystals. Based on SEM analysis, the Zn/ZnO core-shell structures formed by intermittent boiling under induction cooker show a tendency for spherical morphology with stacked and bending ZnO shells while the ones formed by continuous boiling under electric cooker exhibit a spherical morphology with the irregular ZnO nanorods on the surface of Zn spheres, and the continuous boiling can promote the peeling and regeneration of ZnO shells on the surface of Zn cores. The PL spectra of the Zn/ZnO core-shell structures have been recorded at room temperature and observed two peaks around 379 nm and 538 nm. However, the defect emission is much stronger than the UV emission in the Zn/ZnO core-shell structures synthesized under electric cooker.