Ferreira Sanchez Dario, Ihli Johannes, Zhang Damin, Rohrbach Thomas, Zimmermann Patric, Lee Jinhee, Borca Camelia N, Böhlen Natascha, Grolimund Daniel, van Bokhoven Jeroen A, Ranocchiari Marco
Swiss Light Source, Paul Scherrer Institut (PSI), 5232, Villigen, Switzerland.
Laboratory for Catalysis and Sustainable Chemistry, Paul Scherrer Institute, 5232, Villigen PSI, Switzerland.
Angew Chem Int Ed Engl. 2021 Apr 26;60(18):10032-10039. doi: 10.1002/anie.202013422. Epub 2021 Mar 18.
The introduction of structural defects in metal-organic frameworks (MOFs), often achieved through the fractional use of defective linkers, is emerging as a means to refine the properties of existing MOFs. These linkers, missing coordination fragments, create unsaturated framework nodes that may alter the properties of the MOF. A property-targeted utilization of this approach demands an understanding of the structure of the defect-engineered MOF. We demonstrate that full-field X-ray absorption near-edge structure computed tomography can help to improve our understanding. This was demonstrated by visualizing the chemical heterogeneity found in defect-engineered HKUST-1 MOF crystals. A non-uniform incorporation and zonation of the defective linker was discovered, leading to the presence of clusters of a second coordination polymer within HKUST-1. The former is suggested to be responsible, in part, for altered MOF properties; thereby, advocating for a spatio-chemically resolved characterization of MOFs.
在金属有机框架（MOF）中引入结构缺陷，通常通过部分使用有缺陷的连接体来实现，这正成为一种改善现有MOF性能的手段。这些缺少配位片段的连接体产生了不饱和框架节点，可能会改变MOF的性能。这种方法的靶向性能利用需要了解缺陷工程MOF的结构。我们证明全场X射线吸收近边结构计算机断层扫描有助于增进我们的理解。通过可视化在缺陷工程HKUST-1 MOF晶体中发现的化学不均匀性得以证明。发现了有缺陷连接体的非均匀掺入和分区，导致HKUST-1中存在第二种配位聚合物簇。前者被认为部分导致了MOF性能的改变；因此，主张对MOF进行空间化学解析表征。
