On the nature and location of organic template molecules and their effect on the stability and redox properties of microporous CoAlPO-34 catalyst

被引:14
作者
Sankar, G [1 ]
Wyles, JK [1 ]
Catlow, CRA [1 ]
机构
[1] UCL Royal Inst Great Britain, Davy Faraday Res Lab, London W1S 4BS, England
关键词
aluminophosphates; microporous; catalysts; diffraction; EXAFS;
D O I
10.1023/B:TOCA.0000003088.21277.f5
中图分类号
O69 [应用化学];
学科分类号
081704 ;
摘要
Small-pore CoAlPO-34 materials were synthesized with a variety of organic template molecules and were characterized in detail, employing microcrystal diffraction, powder diffraction and in situ combined XRD/XAS techniques. We found that, when two template molecules or two nitrogen atoms of a single template molecule are present inside the chabazitic cage, the concentration of cobalt present in the system is ca. 25 at%, which introduces instability in the framework structure during the removal of the organic template. In contrast, when only one template molecule is present, it is possible to control the concentration of Co(II) ions in the framework to ca. 10 at%; these systems show good structural integrity and redox chemistry that was exploited for the regio-selective conversion of linear alkane molecules.
引用
收藏
页码:173 / 184
页数:12
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