Abstract: Porous silica was prepared with simple organic template and tetraethyl-orthosilicate (TEOS) as pore-generating agent and silicon precursor respectively. The influences of dosage of simple organic template upon the specific surface area and pore volume of the as-made porous silica were investigated. BET, SEM and TEM methods were employed to analyze the specific surface area and pore structure of the silica samples. A proposed mechanism was developed to explain the pore-forming effect of the simple organic template on the porous silica. Parallel experiments with base-silica-sol used as silicon precursor were also conducted to testify the proposed mechanism. The results indicated that when the dosage of the template was 0.3 g/mL TEOS, the samples with large surface area (>650 m2/g) and high pore volume (>1.0 mL/g) could be successfully prepared, and the pore structure was amorphous. It is highly possible that the amorphous pores are generated by the simple organic template which was mixed with TEOS polymer in molecular scale and was burnt away in the following calcination process.

Key words: porous silica, sol-gel, template

摘要： 以简单有机模板为致孔剂、正硅酸乙酯(TEOS)为硅源制备了多孔SiO2，考察了模板剂加入量对样品比表面和孔容的影响，测定了样品的比表面和孔结构，提出了简单有机模板对多孔SiO2的致孔机理，并与以碱性硅溶胶为硅源对比，验证了该机理. 结果表明，简单有机模板添加量为模板剂/TOES=0.3 mg/mL时，样品比表面积可提高至650 m2/g以上，孔容大于1.0 mL/g，孔道为无规则结构. 该多孔结构的产生很可能是因为简单有机模板和TEOS的聚合物发生分子级混合，从而在凝胶和煅烧过程中使样品中产生了丰富的孔道.

关键词: 多孔二氧化硅, 溶胶-凝胶, 模板