Synthesis and visible-light photocatalytic activity of SiC/SiO2 nanochain heterojunctions

SiC/SiO2 nanochains were prepared by a simple chemical vapor reaction method and characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV-vis diffuse reflectance spectroscopy analyses. The visible-light photocatalytic activity of SiC/SiO2 nanochains was investigated by the photocatalytic decomposition of Rhodamine B in the aqueous solution. The results show that the SiC/SiO2 nanochain has equirotal beads of 650 nm and a uniform string with a diameter of 240 nm. The photo-response behavior of the SiC/SiO2 nanochain can be expanded to visible-light region with a high absorbance. The photocatalytic activity of SiC/SiO2 nanochains was found to be better compared to that of the SiO2-free SiC nanowires owing to the nanosized SiO2 coating that can form activated hydroxyl groups and effectively separate the photogenerated electrons and holes.