氨基功能化短孔道有序介孔材料H_2N-Zr-Ce-SBA-15的合成及吸附性能

以pluronic(P123)为模板剂,正硅酸乙酯(TEOS)为硅源,氯化氧锆和硝酸亚铈为无机前驱盐,N-(2-氨乙基)-3-氨丙基三甲氧基硅烷(AAPTS)为硅烷化试剂,采用后接枝法合成了氨基功能化六方板状短孔道有序介孔材料H2N-Zr-Ce-SBA-15(H2N-ZCS).采用小角X射线衍射(LXRD)、傅里叶变换红外(FTIR)光谱、透射电子显微镜(TEM)、扫描电子显微镜(SEM)、热重分析、N2吸附/脱附等手段对H2N-ZCS进行了表征.结果表明AAPTS成功地嫁接到有序介孔材料上,H2N-ZCS仍保持了类似于传统SBA-15高度有序的二维六方相介孔结构,且孔道方向垂直于该六方板面.对阴离子染料酸性品红吸附实验表明,H2N-ZCS比H2N-SBA-15具有较强的吸附能力.这种功能化短孔道、大径轴比的六方板状介孔材料在吸附、分离及催化等领域中能更有效地促进分子的扩散传递.

Synthesis and Adsorption Properties of Amino-Functionalized H2N-Zr-Ce-SBA-15 Mesoporous Materials with Short Mesochannels

Amino-functionalizedH2N-Zr-Ce-SBA-15 (H2N-ZCS)mesoporousmaterialswith unique hexagonal platelet morphologies and short channels were synthesized by a post-grafting method using [1-(2-amino-ethyl)-3-aminopropyl] trimethoxysilane (AAPTS) and tetraethyl orthosilicate (TEOS) as a silica source, zirconyl chloride and cerous nitrate as precursors, and pluronic P123 triblock copolymer as a structure directing agent. The as-synthesized materials were characterized by low-angle X-ray diffraction (LXRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetry (TG), and N2 adsorption/desorption isotherms. Characterization revealed that the functionalized H2N-ZCS mesoporous materials have unique hexagonal platelet morphologies with short channels and they possess a highly ordered two-dimensional hexagonal mesoporous structure similar to conventional SBA-15. The uptake of anionic dye onto the organic functionalized H2N-ZCS and H2N-SBA-15 were compared. The results demonstrate that H2N-ZCS materials have higher adsorption rates and adsorption capacities compared with H2N-SBA-15. The resultant H2N-ZCS materials with short channels are superior to conventional SBA-15 in terms of fiber morphology facilitating molecular diffusion when used in adsorption, separation, and catalytic processes.