Fan Wei, Morozumi Kazumasa, Kimura Riichiro, Yokoi Toshiyuki, Okubo Tatsuya
Department of Chemical System Engineering, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan.
Langmuir. 2008 Jun 1;24(13):6952-8. doi: 10.1021/la703838j. Epub 2008 May 29.
Aggregates (80 nm) of sodalite nanocrystals with crystallite sizes ranging from 20 to 40 nm have been synthesized from a sodium aluminosilicate solution at low temperature, without adding any organic additives, while paying attention to the key factors for the synthesis of nanosized zeolite crystals. The physical properties of nanosized sodalite crystals were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, 29Si solid-state magic-angle spinning (MAS) NMR, and N2 adsorption. As expected, the external surface area of nanosized sodalite crystals is significantly increased compared with that of microsized sodalite crystals. The size of synthesized sodalite crystals can be controlled from 20 nm to 10 microm. It is found that the preparation of a homogeneous aluminosilicate solution followed by the formation of an aluminosilicate hard gel by adjusting the initial composition, for example, SiO2/Al2O3 and Na2O/H2O ratios, is critical for synthesis.
已在低温下由硅铝酸钠溶液合成了微晶尺寸为20至40纳米的方钠石纳米晶体聚集体（80纳米），未添加任何有机添加剂，同时关注了纳米尺寸沸石晶体合成的关键因素。通过X射线衍射、扫描电子显微镜、高分辨率透射电子显微镜、29Si固体魔角旋转（MAS）核磁共振和N2吸附对纳米尺寸方钠石晶体的物理性质进行了表征。正如预期的那样，与微米尺寸的方钠石晶体相比，纳米尺寸方钠石晶体的外表面积显著增加。合成的方钠石晶体尺寸可控制在20纳米至10微米之间。发现制备均匀的硅铝酸盐溶液，然后通过调整初始组成（例如SiO2/Al2O3和Na2O/H2O比率）形成硅铝酸盐硬凝胶，对于合成至关重要。
