Role of SiOx on the photoluminescence properties of β-SiC

Abstract

The present work reports the formation of nanostructured β-SiC by carbothermal reduction using mesoporous silica (SBA-15) and furfuryl alcohol as the precursors. While the synthesized SiC nanowire has a mean diameter of 55nm with several micrometers in length, the SiC nanoparticle has a mean diameter of 40nm. The possible growth mechanism for nanostructured SiC is also discussed from the point of thermodynamics. TEM images show that the β-SiC is covered with a layer (SiOx) of 1.86nm thickness. XPS spectra indicate that the amorphous layer (SiOx) is reduced from 45.08 to 9.97% during the alkaline treatment. The PL spectrum of as-synthesized β-SiC shows that the emission peaks at different wavelength (404.2, 444.8, 479.8, 494.9, 511.9 and 520.1nm), which are mainly due to the presence of defects in the SiOx layer. These results are expected to make β-SiC as a promising material in optoelectronic devices.