以正硅酸乙酯(TEOS)和仲丁醇铝(ASB)为硅源和铝源,采用溶胶-凝胶和超临界干燥工艺制备出了高比表面积的Al2O3-SiO2块状气凝胶,研究了不同溶胶配比及热处理温度对气凝胶结构的影响,利用红外光谱、氮气吸附、X射线衍射和扫描电子显微镜等手段对气凝胶的性能和鲒构进行了分析.结果表明,随Al/Si摩尔比增大,Al2O3-SiO2气凝胶凝胶时间逐渐缩短,比表面积(1000℃)先增后减,当Al/Si摩尔比为4∶1时,比表面积最高,为444.5m2/g;1200℃,Al/Si为8∶1时比表面积最高,为115m2/g,具有较好的高温热稳定性.红外分析表明Al2O3-SiO2气凝胶存在Al-O-Si键;在1000℃热处理后,Al2O3-SiO2气凝胶中Si含量减少到一定程度才会出现γ-Al2O3.通过SEM观察表明Al2O3-SiO2气凝胶粒子较Al2O3气凝胶小.
参考文献
| [1] | Hrubesh LW. .Aerogel applications[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,1998(1):335-342. |
| [2] | Schmidt M.;Schwertfeger F. .Applications for silica aerogel products[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,1998(1):364-368. |
| [3] | 秦国彤,门薇薇,魏微,李大鹏.气凝胶研究进展[J].材料科学与工程学报,2005(02):293-296. |
| [4] | 陈龙武;甘礼华.气凝胶[J].化学通报(印刷版),1997(08):21. |
| [5] | Himmel B;Gerber Th;Burger H et al.Structural characterization of SiO2-Al2O3 aerogels[J].Journal of Non-Crystalline Solids,1995,186:149. |
| [6] | Poco JF.;Hrubesh LW.;Satcher JH. .Synthesis of high porosity, monolithic alumina aerogels[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,2001(1/3):57-63. |
| [7] | 岳宝华,周仁贤,郑小明.制备条件对SiO2改性氧化铝材料耐热性能的影响[J].无机化学学报,2007(03):533-536. |
| [8] | Kim SM;Lee YJ;Jun KW;Park JY;Potdar HS .Synthesis of thermo-stable high surface area alumina powder from sol-gel derived boehmite[J].Materials Chemistry and Physics,2007(1):56-61. |
| [9] | Osaki T;Nagashima K;Watari K;Tajiri K .Silica-doped alumina cryogels with high thermal stability[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,2007(24/25):2436-2442. |
| [10] | Poco JF.;Hrubesh LW.;Satcher JH. .Synthesis of high porosity, monolithic alumina aerogels[J].Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites,2001(1/3):57-63. |
| [11] | Hyun S.H.;Kim J.J. .Synthesis and Characterization of Low-Dielectric Silica Aerogel Films[J].Journal of the American Ceramic Society,2000(3):533-540. |
| [12] | Aravind, PR;Mukundan, P;Pillai, PK;Warrier, KGK .Mesoporous silica-alumina aerogels with high thermal pore stability through hybrid sol-gel route followed by subcritical drying[J].Microporous and Mesoporous Materials,2006(1/3):14-20. |
| [13] | Horiuchi T.;Osaki T.;Sugiyama T.;Suzuki K.;Mori T.;Chen L. .A novel alumina catalyst support with high thermal stability derived from silica-modified alumina aerogel[J].Catalysis Letters,1999(2/3):89-92. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%