| 制备高比表面积碳化硅的几种影响因素 |
| Factors Affecting Preparation of High Specific Surface Area Silicon Carbide |
|
| 摘要: 采用溶胶凝胶法，以蔗糖和正硅酸乙酯(TEOS)为原料，草酸为TEOS水解的催化剂，制备均相碳化硅前驱体，在氩气氛和高温条件下(1 350～1 600 ℃)将碳化硅先驱体进行碳热还原，制备出高比表面积的SiC。考察了水/TEOS物质的量的比、碳/硅物质的量的比及镍盐等因素对碳化硅比表面积的影响。结果表明，当nwater/nTEOS=7.5，nC/nSi=4时，适宜的镍催化剂(nNi/nTEOS=0.005)，凝胶形成的时间最短，镍盐的加入可使碳热还原温度降低200 ℃。 |
| 关键词: 溶胶-凝胶 碳化硅 碳热还原 高比表面积 |
| 基金项目: |
| Abstract: A sol-gel process catalyzed by oxalic acid was used for the preparation of SiC precursor from raw materials of tetraethyl orthosilicate (TEOS) and sucrose. The precursor thus obtained was homogeneous. Sintered with a certain heating program (1 350～1 600 ℃) in an argon flow, the precursor was converted into the high surface area SiC. The effect of the amount of water, nickel nitrate and the molar ratio of C/Si on the surface area of SiC were studied. The results show that when the molar ratio of H2O/TEOS, C/Si and nickel nitrate/TEOS is 7.5, 4, 0.005, respectively, the gel formation time is the shortest. The temperature for carbothermal reduction could be lowered by 200 ℃ when the nickel nitrate is added into the precursor. |
| Keywords: sol-gel silicon carbide carbothermal reduction high specific surface area |
| |
| 摘要点击次数: 1172 |
| 全文下载次数: 1950 |
| 林建新,郑勇,郑瑛,魏可镁.制备高比表面积碳化硅的几种影响因素[J].无机化学学报,2006,22(10):1778-1782. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| Support information: |
|
|
|
|
|
|
