Construction and in-cage modification of metal-organic polyhedra based on Anderson-like polyoxovanadate clusters

Abstract

Two tetrahedral metal-organic polyhedra (MOPs) constructed from Anderson-like alkoxo-polyoxovanadate clusters, [NH₂Me₂]₈{[V₆O₆(OCH₃)₉(SO₄)]₄(2,6-NDC)₆}(MeOH)₁₅(DMA)₉ (1) and [NH₂Me₂]₈{[V₆O₆(OCH₃)₉(C₆H₅PO₃)]₄(2,6-NDC)₆}(MeOH)₉(DMA)₁₀ (2), were synthesized under solvothermal conditions. They are isomorphic tetrahedra composed of 3-connected [V₆O₆(OCH₃)₉(X)] SBUs and rigid bidentate ligand 2,6-naphthalenedicarboxylic acid (NDC). The difference between the two structures is modification of the inner cage in 2 by introduction of phenylphosphonic acid. The space inside the molecular cage was reduced from 1100 ų to 700 ų after introduction of phenylphosphonic acid, as calculated by the VIODOO program. Interestingly, the iodine adsorption performance of 2 was improved by more than three times compared to 1 after the introduction of phenylphosphonic acid. These findings may provide new insights into the modification and functionalization within the cage of MOPs.

Graphical Abstract

Keywords:

• Metal-organic polyhedron
• molecular cage
• crystal structure
• functionalization
• iodine adsorption

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the NSFC (No. 22101067), the Natural Science Foundation of Hainan Province (221QN169), Start-up Research Foundation of Hainan University (KYQD(ZR)-20008). National Natural Science Foundation of China.