不同碳硅比对合成高比表面积碳化硅的影响

Effect of n(C)/n(Si) on the Synthesis of High Surface Area SiC

以淀粉和工业水玻璃为原料,经过碳热还原反应制备出碳化硅纳米线。采用XRD、SEM、氮吸附-脱附和荧光光谱仪(PL)对所制备的样品进行表征,同时考察了碳硅比(物质的量比,下同)对碳化硅形貌、比表面积和荧光性能的影响。结果表明,当碳硅比为4.5时,合成的碳化硅为直的纳米线,比表面积为45m2/g,发光强度也达到最大。

SiC nanowires were prepared by carbothermal reduction method, in which starch and water glass were employed as carbon and silica precursors respectively. The as-synthesized SiC was characterized by XRD, SEM, N2 absorption-desorption and photoluminescence, and the effects of n（C）/n（Si） on the morphology, surface area and photoluminescenee property of SiC were investigated. When molar ratio of carbon to silicon in the precursors is equal to 4. 5, obtained SiC is straight nanowires, with the specific surface area up to 45m^2/g and the intensity of light emission reaches maximum.