Influence of Si species on intergrowth and anisotropic crystal growth of silicalite-1
Influence of Si species on intergrowth and anisotropic crystal growth of silicalite-1
复制标题
Si物种对silicalite-1共生和各向异性晶体生长的影响
DOI：
10.1007/s10934-013-9779-y
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
and Y. Ohya
中科院分区：
文献类型：
--
作者：
T. Ban;S. Ohishi;and Y. Ohya
以不同条件下制备的硅胶为原料，水热合成了Silicalite-1晶体。考察了硅胶中硅物种的状态以及反应溶胶中硅酸盐离子和模板剂的浓度对Silicalite-1晶体生长的影响。硅物种高度缩合的硅胶有利于硅沸石-1晶体的共生，而硅物种的低缩合程度则导致棺材状晶体的生长。因此，硅物种的缩合程度对Silicalite-1晶体的共生有显著影响。此外，在较低的硅酸盐浓度下，得到了沿c轴伸长的Silicalite-1晶体。随着反应溶胶中硅酸盐浓度的增加，Silicalite-1的长径比减小。此外，随着模板剂N(C3H7)4+用量的减少，Silicalite-1晶体各向同性变大。因此，Silicalite-1晶体的生长方向取决于反应溶胶中硅酸盐离子的浓度，而不是N(C3H7)4+的浓度。
Silicalite-1 crystals were hydrothermally synthesized from silica gels prepared under different conditions. The influence of the state of Si species in the silica gels and the concentrations of silicate ions and a template agent in the reaction sols on crystal growth of silicalite-1 was examined. The use of silica gels with a high degree of condensation of Si species resulted in the intergrowth of silicalite-1 crystals, whereas a low degree of condensation of Si species led to coffin-shaped crystals. Thus, the degree of condensation of Si species had significant influence on the intergrowth of silicalite-1 crystals. Moreover, at a low silicate concentration, silicalite-1 crystals elongated along thec-axis were obtained. With increasing silicate concentration in the reaction sols, the aspect ratio of silicalite-1 decreased. Furthermore, with decreasing the amount of N(C3H7)4+used as a template agent, the silicalite-1 crystals became larger isotropically. Thus, the growth direction of silicalite-1 crystals was dependent on silicate ion concentration in the reaction sols, but not on N(C3H7)4+concentration.