Department of Chemistry, Clemson University, Clemson, SC 29634, USA.
NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA.
Angew Chem Int Ed Engl. 2023 Jun 26;62(26):e202303819. doi: 10.1002/anie.202303819. Epub 2023 Apr 26.
Two-dimensional graphitic metal-organic frameworks (GMOF) often display impressive electrical conductivity chiefly due to efficient through-bond in-plane charge transport, however, less efficient out-of-plane conduction across the stacked layers creates large disparity between two orthogonal conduction pathways and dampens their bulk conductivity. To address this issue and engineer higher bulk conductivity in 2D GMOFs, we have constructed via an elegant bottom-up method the first π-intercalated GMOF (iGMOF1) featuring built-in alternate π-donor/acceptor (π-D/A) stacks of Cu -coordinated electron-rich hexaaminotriphenylene (HATP) ligands and non-coordinatively intercalated π-acidic hexacyano-triphenylene (HCTP) molecules, which facilitated out-of-plane charge transport while the hexagonal Cu (HATP) scaffold maintained in-plane conduction. As a result, iGMOF1 attained an order of magnitude higher bulk electrical conductivity and much smaller activation energy than Cu (HATP) (σ=25 vs. 2 S m , E =36 vs. 65 meV), demostrating that simultaneous in-plane (through-bond) and out-of-plane (through πD/A stacks) charge transport can generate higher electrical conductivity in novel iGMOFs.
二维石墨状金属有机骨架(GMOF)通常表现出令人印象深刻的电导率,主要归因于有效的面内键间电荷传输,然而,堆叠层之间的面外传导效率较低,导致两个正交传导途径之间存在巨大差异,从而抑制了其体电导率。为了解决这个问题并在 2D GMOF 中实现更高的体电导率,我们通过巧妙的自下而上方法构建了第一个具有内置交替π供体/受体(π-D/A)堆叠的π-插层 GMOF(iGMOF1),其特征是 Cu 配位的富电子六氨基三联苯(HATP)配体和非配位插层的π-酸性六氰基三联苯(HCTP)分子,这促进了面外电荷传输,同时六方 Cu(HATP)支架保持面内传导。结果,iGMOF1 的体电导率比 Cu(HATP)高一个数量级,活化能小得多(σ=25 对 2 S m ,E =36 对 65 meV),表明新型 iGMOF 中同时进行面内(键间)和面外(通过 π-D/A 堆叠)电荷传输可以产生更高的电导率。