【摘要】 以Fe为催化剂,采用溶胶-凝胶和碳热还原的方法,制备出具有不同尺寸、不规则的-βS iC颗粒,并用XRD,FTIR,SEM和BET等分析手段对其进行结构表征。结果表明:在1 300℃氩气氛中,不使用Fe催化剂,由酚醛树脂和正硅酸乙酯制成的干凝胶经碳热还原不能形成-βS iC,产物主要是无定形炭和S iO2;而使用Fe催化剂制成的干凝胶则可形成-βS iC。此外,随着Fe用量的增加,-βS iC的颗粒尺寸和平均晶粒度增加,而堆积缺陷密度和比表面积则减小。更多还原

【Abstract】 Irregular β-SiC particles were prepared by a sol-gel and carbothermal reduction route,in which(tetraethoxysilane) and phenolic resin were employed to prepare carbonaceous silicon xerogels,the precursor of the SiC.The samples were characterized by XRD,FTIR,SEM and BET.Results indicated that β-SiC was not produced in the solgel process in the absence of Fe-catalyst and the existence of Fe enhanced the formation of(β-SiC).With an increase in the amount of Fe catalyst,the average crystallite size of the SiC particles increased,whereas the stacking fault density and the surface area decreased.更多还原