溶胶-凝胶中Fe催化剂用量对β-SiC堆积缺陷和形貌的影响  

Effects of the amounts of Fe catalyst on stacking faults and morphologies of β-SiC

作　　者：武向阳[1] 靳国强[1] 郭向云[1] 

机构地区：[1]中国科学院山西煤炭化学研究所煤转化国家重点实验室

出　　处：《新型炭材料》2005年第4期324-328,共5页New Carbon Materials

基　　金：国家自然科学基金(20471067;20403027);山西省自然科学基金(20031031)~~

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。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, FFIR, SEM and BET. Results indicated that β-SiC was not produced in the sol-gel 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.

关 键 词：溶胶-凝胶 碳热还原 Β-SIC 平均晶粒度 Fe催化剂 

分 类 号：O613.72[理学—无机化学]