Aluminum ion occupancy in the structure of synthetic saponites: Effect on crystallinity
Aluminum ion occupancy in the structure of synthetic saponites: Effect on crystallinity
复制标题
合成皂石结构中铝离子的占据：对结晶度的影响
DOI：
10.2138/am.2014.4543
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发表时间：
2014
影响因子：
3.1
通讯作者：
Zhu Runliang
中科院分区：
文献类型：
--
作者：
He Hongping;Li Tian;Tao Qi;Chen Tianhu;Zhang Dan;Zhu Jianxi;Yuan Peng;Zhu Runliang
摘要采用水热法合成了固定（Si+Al）/Mg和Si/Mg比的两个系列皂石。采用XRD、XRF、27 Al和29 Si MAS NMR、SEM和TEM对产物进行了表征。XRD图谱表明，在初始Si/Al比为5.43-7.89的范围内得到了有序的皂石。超过该Si/Al比范围，获得具有小结晶颗粒的不良结晶皂石，这可以从TEM图像中看出。当用表面活性剂插层皂石时，插层产物显示出强烈且有序的（00 l）反射，表明本研究成功地合成了层状皂石。27 Al MAS NMR谱表明，结晶良好的合成皂石比结晶不良的合成皂石具有更高的Al（IV）/Al（VI）比值，这是影响合成皂石结晶度的重要因素。一对一替换（即，1 Al ~（3+）→ 1 Mg ~（2+）的取代对合成皂石的结晶度有负面影响。在用硅烷接枝合成皂石之后，在-86ppm处的29 Si NMR信号的强度降低以及Q3 Si（0Al）和Q3 Si（1Al）信号的强度增加强烈地表明在约86 ppm处的信号降低。~ 86 ppm对应于皂石层边缘处的Q2 Si。
Abstract Two series of saponites with fixed (Si+Al)/Mg and Si/Mg ratios, respectively, were synthesized by using hydrothermal methods. The obtained products were characterized by XRD, XRF, 27Al, and 29Si MAS NMR, SEM, and TEM. XRD patterns showed that well-ordered saponites were obtained in the initial Si/Al ratio range of 5.43-7.89. Beyond this Si/Al ratio range, poorly crystallized saponites were obtained with small crystallized particles, which can be seen from TEM images. When intercalating saponite with surfactant, the intercalated products displayed strong and well-ordered (00l) reflections, indicating that layered saponite has been successfully synthesized in the present study. 27Al MAS NMR spectra demonstrated that well-crystallized synthetic saponites had a higher Al(IV)/Al(VI) ratio than the poorly crystallized samples, which is an important factor affecting the crystallinity of synthetic saponite. A one-to-one substitution (i.e., 1 Al3+ → 1 Mg2+) actually occurred in the octahedral sheet and this substitution had a negative effect on the crystallinity of the synthetic saponites. After grafting the synthetic saponites with silane, the decreased intensity of the 29Si NMR signal at -86 ppm and the increased intensity of Q3 Si(0Al) and Q3 Si(1Al) signals strongly suggested that the signal at ca. -86 ppm corresponded to Q2 Si at the layer edges of saponite.
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影响因子：
5.6
作者：
He, Hongping;Ma, Yuehong;Qing, Yanhong
通讯作者：
Qing, Yanhong
影响因子：
3.1
作者：
D. Woessner
通讯作者：
D. Woessner
影响因子：
3.7
作者：
M. Casagrande;L. Storaro;M. Lenarda;S. Rossini
通讯作者：
M. Casagrande;L. Storaro;M. Lenarda;S. Rossini
影响因子：
--
作者：
E. Giannelis;R. Krishnamoorti;E. Manias
通讯作者：
E. Giannelis;R. Krishnamoorti;E. Manias
影响因子：
9.9
作者：
Daniel, Lisa M.;Frost, Ray L.;Zhu, Huai Yong
通讯作者：
Zhu, Huai Yong