Department of Chemical Engineering, University of California, Davis, California 95616, USA.
Faraday Discuss. 2017 Sep 8;201:195-206. doi: 10.1039/c7fd00031f.
The metal-organic framework NU-1000, with Zr-oxo, hydroxo, and aqua nodes, was modified by incorporation of hydroxylated Al(iii) ions by ALD-like chemistry with [Al(CH)(iso-propoxide)] followed by steam (ALD = atomic layer deposition). Al ions were installed to the extent of approximately 7 per node. Single-site iridium diethylene complexes were anchored to the nodes of the modified and unmodified MOFs by reaction with Ir(CH)(acac) (acac = acetylacetonate) and converted to Ir(CO) complexes by treatment with CO. Infrared spectra of these supported complexes show that incorporation of Al weakened the electron donor tendency of the MOF. Correspondingly, the catalytic activity of the initial supported iridium complexes for ethylene hydrogenation increased, as did the selectivity for ethylene dimerization. The results of density functional theory calculations with a simplified model of the nodes incorporating Al(iii) ions are in qualitative agreement with some catalyst performance data.
具有 Zr-氧、羟和水节点的金属有机骨架 NU-1000 通过 ALD 样化学方法用 [Al(CH)(异丙氧基)] 与羟基化的 Al(iii)离子进行改性，然后进行蒸汽处理 (ALD = 原子层沉积)。Al 离子的安装量约为每个节点 7 个。通过 Ir(CH)(acac)（acac = 乙酰丙酮酸盐）与改性和未改性 MOF 的节点反应，将单原子铱二乙烯配合物锚定在节点上，并通过与 CO 反应转化为 Ir(CO)配合物。这些负载配合物的红外光谱表明，Al 的掺入削弱了 MOF 的电子给体倾向。相应地，初始负载铱配合物对乙烯加氢的催化活性增加，乙烯二聚体的选择性也增加。带有简化的 Al(iii)离子节点模型的密度泛函理论计算结果与一些催化剂性能数据定性一致。
