Abstract：
Supramolecular coordination self-assembly on solid surfaces provides an effective route to form two-dimensional (2D) metal-organic frameworks (MOFs). In such processes, surface-adsorbate interaction plays a key role in determining the MOFs\' structural and chemical properties. Here, we conduct a systematic study of Cu-HAT (HAT = 1,4,5,8,9,12-hexaazatriphenylene) 2D conjugated MOFs (c-MOFs) self-assembled on Cu(111), Au(111), Ag(111), and MoS2 substrates. Using scanning tunneling microscopy and density functional theory calculations, we found that the as-formed Cu3HAT2 c-MOFs on the four substrates exhibit distinctive structural features including lattice constant and molecular conformation. The structural variations can be attributed to the differentiated substrate effects on the 2D c-MOFs, including adsorption energy, lattice commensurability, and surface reactivity. Specifically, the framework grown on MoS2 is nearly identical to its free-standing counterpart. This suggests that the 2D van der Waals (vdW) materials are good candidate substrates for building intrinsic 2D MOFs, which hold promise for next-generation electronic devices.
摘要：
在固体表面上的超分子配位自组装提供了形成二维（2D）金属有机框架（MOF）的有效途径。在这些过程中,表面-吸附物相互作用在确定MOFs的结构和化学性质中起关键作用。这里,我们对Cu(111)上自组装的Cu-HAT(HAT=1,4,5,8,9,12-六氮杂亚苯)2D共轭MOFs(c-MOFs)进行了系统的研究,Au(111),Ag(111),和MoS2基板。利用扫描隧道显微镜和密度泛函理论计算，我们发现在四个基底上形成的Cu3HAT2c-MOFs表现出独特的结构特征，包括晶格常数和分子构象。结构变化可以归因于对2Dc-MOF的不同底物效应，包括吸附能，晶格可约性，和表面反应性。具体来说,在MoS2上生长的框架几乎与其独立的对应物相同。这表明2D范德华（vdW）材料是构建固有2DMOF的良好候选基底，为下一代电子设备提供了希望。
