Large-scale synthesis of Si3N4 nanowires by a modified carbothermal reduction method using graphite felt as growth substrate

Abstract

In this work, silicon nitride nanowires (Si3N4NWs) were successfully prepared by a modified carbothermal reduction method, using graphite felt as a growth substrate and in the absence of the catalysts. The synthesized Si3N4NWs exhibited smooth surface, uniform morphology and high aspect ratios. The high purity and high crystallinity of Si3N4NWs were confirmed by XRD, XPS, etc. More importantly, the vapor–solid (VS) growth mechanism of Si3N4NWs was proposed. It is indicated that the graphite felt played a crucial role in increasing the proportion of the gas-phase reaction to obtain large-scale Si3N4NWs. The Si3N4NWs produced by this approach have the advantages of high yield, high purity and low cost, which are very prospective for application.