Ligand Symmetry Modulation for Designing a Mesoporous Metal-Organic Framework: Dual Reactivity to Transition and Lanthanide Metals for Enhanced Functionalization

A promising alternative strategy for designing mesoporous metal-organic frameworks (MOFs) has been proposed, by modifying the symmetry rather than expanding the length of organic linkers. By means of this approach, a unique MOF material based on the target [Zn-8(ad)(4)] (ad=adeninate) clusters and C-3-symmetric organic linkers can be obtained, with trigonal microporous (ca., 0.8 nm) and hexagonal mesoporous (ca., 3.0 nm) 1D channels. Moreover, the resulting 446-MOF shows distinct reactivity to transition and lanthanide metal ions. Significantly, the transmetalation of Co-II or Ni-II on the Zn-II centers in 446-MOF can enhance the sorption capacities of CO2 and CH4 (16-21 %), whereas the impregnation of Eu-III and Tb-III in the channels of 446-MOF will result in adjustable light-emitting behaviors.