尿素-过氧化氢混合模板法合成介孔二氧化硅

以尿素-过氧化氢为混合模板、正硅酸乙酯为硅源,在酸性条件下,通过溶胶-凝胶过程合成二氧化硅介孔材料。采用煅烧法除去模板剂,用红外光谱、XRD、N2吸附-脱附、HRTEM等分析测试手段对介孔材料的结构和形态进行了表征。结果表明:与以尿素为单一模板相比,采用混合模板剂所合成介孔材料为蠕虫状,孔径分布基本保持不变、比表面积相近(分别为445、431m2/g)、孔径(分别为7.04、8.11nm)和孔体积(分别为0.783、0.874cm3/g)明显增大。

Synthesis of Mesoporous Silica Materials via Urea-H2O2 Co-templated Sol-gel Reactions

The mesoporous silica materials were prepared using urea-H2O2 as mixt-templates and TEOS as silica source via HCl-catalyzed sol -gel process,followed by removing the pore-forming agents by calcination. The materials were characterized by FT-IR,nitrogen sorption isotherm,powder X-ray diffraction,HRTEM for structure and morpha. The results indicated that the materials prepared using urea -H2O2 as co-templates were amorphous,had almost the same specific surface areas (e.g. 445 m2/g→431 m2/g) and pore size distributions as well as larger pore volumes(e.g. 0.783 cm3/g →0.874cm3/g)andporediameter(e.g.7.04nm→8.11nm)thanthemesoporous silica materials prepared using urea as single-template.