Ferromagnetic ZnO bicrystal nanobelts fabricated in low temperature

摘要

Zinc oxide bicrystal nanobelts were fabricated via a vapor phase transport of a powder mixture of Zn, BiI_3, and MnCl_2·H_2O at temperatures as low as 300 ℃. The bicrystal nanobelts, growing along the [0113] direction, have the widths of 40-150 nm and lengths of tens of microns. The energy dispersive x-ray spectroscopy result verifies that the bicrystal nanobelts contain higher concentration of both Bi and Mn along the grain boundary. The investigation of the growth mechanism proposes that MnBi may induce the formation of bicrystal nanobelts. Photoluminescence spectra show that the ultraviolet emission of the bicrystal nanobelts has a blueshift of 18 meV as compared to Bi-ZnO nanowires at 10 K. The bicrystal nanobelts also exhibit ferromagnetism at room temperature.