A heterobimetallic cobalt–aluminum complex was immobilized onto the metal organic framework NU-1000 using a simple solution-based deposition procedure. Characterization data are consistent with a maximum loading of a single Co–Al complex per Zr6 node of NU-1000. Furthermore, the data support that the Co–Al bimetallic complex is evenly distributed throughout the NU-1000 particle, binds covalently to the Zr6 nodes, and occupies the NU-1000 apertures with the shortest internode distances (∼8.5 Å). Heating the anchored Co–Al complex on NU-1000 at 300 °C for 1 h in air completely removes the organic ligand of the complex without affecting the structural integrity of the MOF support. We propose that a Co–Al oxide cluster is formed in place of the anchored complex in NU-1000 during heating. Collectively, the results suggest that well-defined heterobimetallic complexes can be effective precursors for installing two different metals simultaneously onto a MOF support. The CoAl-functionalized NU-1000 samples catalyze the oxidation of benzyl alcohol to benzaldehyde with tert-butyl hydroperoxide as a stoichiometric oxidant. Density functional theory calculations were performed to elucidate the detailed structures of the Co–Al active sites on the Zr6-nodes, and a Co-mediated catalytic mechanism is proposed.
使用简单的基于溶液的沉积程序将异双
金属
钴铝络合物固定在
金属有机框架 NU-1000 上。表征数据与 NU-1000 的每个 Zr6 节点单个 Co-Al 复合物的最大负载量一致。此外,数据支持 Co-Al 双
金属复合物均匀分布在整个 NU-1000 颗粒中,与 Zr6 节点共价结合,并占据 NU-1000 孔径,节间距离最短(~8.5 Å)。将锚定在 NU-1000 上的 Co-Al 络合物在空气中于 300 °C 加热 1 小时,可完全去除络合物的有机
配体,而不影响 MOF 载体的结构完整性。我们建议在加热过程中形成 Co-Al 氧化物簇来代替 NU-1000 中的锚定复合物。总的来说,结果表明,明确的异双
金属配合物可以成为将两种不同
金属同时安装到 MOF 载体上的有效前体。 CoAl 官能化的 NU-1000 样品以叔
丁基氢过氧化物作为
化学计量氧化剂催化
苯甲醇氧化为
苯甲醛。通过密度泛函理论计算来阐明 Zr6 节点上 Co-Al 活性位点的详细结构,并提出了 Co 介导的催化机制。