An effective strategy to boost the robustness of metal–organic frameworks via introduction of size-matching ligand braces

Abstract

Framework fragility upon the removal of guest solvent molecules has remained an issue for a substantial amount of metal–organic frameworks (MOFs). To address this issue, in this work we illustrate a strategy for the introduction of size-matching ligands as braces that are deliberately anchored onto the open metal sites to support and segment the pores thereby boosting the framework robustness. This is exemplified by employing 4,4′-bipyridine as a brace to bridge two trigonal prismatic clusters of Co₃(μ₃-O)(COO)₆, generating a robust MOF that exhibits permanent porosity and selective gas adsorption behaviors.