Synthesis of nanostructured MgO powders with photoluminescence by plasma-intensified pyrohydrolysis process of bischofite from brine

Abstract

Nanostructured MgO powders were synthesized by an ultra-high temperature pyrohydrolysis process of bischofite (MgCl2·6H2O) in a radio frequency (RF) induction thermal plasma system. The structure, morphology and optical properties were characterized by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. The results showed that MgO nanopowders with two different morphologies were fabricated: near spherical MgO nanoparticles with size in the range of 20~40 nm and 1D nanobelts with a width of about 100 nm. The photoluminescence (PL) studies showed that both of these two kinds of nanostructured MgO powders exhibited a strong ultraviolet-green PL emission under the excitation of 325 nm He-Ne laser.