A robust ultra-microporous cationic aluminum-based metal-organic framework with a flexible tetra-carboxylate linker

Shyamapada Nandi; Asma Mansouri; Iurii Dovgaliuk; Philippe Boullay; Gilles Patriarche; Ieuan Cornu; Pierre Florian; Georges Mouchaham; Christian Serre

doi:10.1038/s42004-023-00938-x

A robust ultra-microporous cationic aluminum-based metal-organic framework with a flexible tetra-carboxylate linker

Commun Chem. 2023 Jul 6;6(1):144. doi: 10.1038/s42004-023-00938-x.

Authors

Shyamapada Nandi^{1

2}, Asma Mansouri¹, Iurii Dovgaliuk¹, Philippe Boullay³, Gilles Patriarche⁴, Ieuan Cornu⁵, Pierre Florian⁵, Georges Mouchaham⁶, Christian Serre⁷

Affiliations

¹ Institut des Matériaux Poreux de Paris, Ecole Normale Supérieure, ESPCI Paris, CNRS, PSL University, 75005, Paris, France.
² Chemistry Division, School of Advanced Sciences, Vellore Institute of Technology, 600127, Chennai, India.
³ Normandie Université, ENSICAEN, UNICAEN, CNRS, CRISMAT, 14050, Caen, France.
⁴ Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies, 91120, Palaiseau, France.
⁵ Centre National de la Recherche Scientifique (CNRS), UPR3079 CEMHTI, Université d'Orléans, 1D Av. Recherche Scientifique, CEDEX 2, 45071, Orléans, France.
⁶ Institut des Matériaux Poreux de Paris, Ecole Normale Supérieure, ESPCI Paris, CNRS, PSL University, 75005, Paris, France. georges.mouchaham@ens.psl.eu.
⁷ Institut des Matériaux Poreux de Paris, Ecole Normale Supérieure, ESPCI Paris, CNRS, PSL University, 75005, Paris, France. christian.serre@ens.psl.eu.

Abstract

Al-based cationic metal-organic frameworks (MOFs) are uncommon. Here, we report a cationic Al-MOF, MIP-213(Al) ([Al₁₈(μ₂-OH)₂₄(OH₂)₁₂(mdip)₆]6Cl·6H₂O) constructed from flexible tetra-carboxylate ligand (5,5'-Methylenediisophthalic acid; H₄mdip). Its crystal structure was determined by the combination of three-dimensional electron diffraction (3DED) and high-resolution powder X-ray diffraction. The structure is built from infinite corner-sharing chains of AlO₄(OH)₂ and AlO₂(OH)₃(H₂O) octahedra forming an 18-membered rings honeycomb lattice, similar to that of MIL-96(Al), a scarce Al-polycarboxylate defective MOF. Despite sharing these structural similarities, MIP-213(Al), unlike MIL-96(Al), lacks the isolated μ₃-oxo-bridged Al-clusters. This leads to an ordered defective cationic framework whose charge is balanced by Cl^- sandwiched between two Al-trimers at the corner of the honeycomb, showing strong interaction with terminal H₂O coordinated to the Al-trimers. The overall structure is endowed by a narrow quasi-1D channel of dimension ~4.7 Å. The Cl^- in the framework restrains the accessibility of the channels, while the MOF selectively adsorbs CO₂ over N₂ and possesses high hydrolytic stability.