Enhancement of photocatalytic performance in two pillared metal–organic framework by solvent-assisted ligand exchange

As a class of newly developed porous solids, metal−organic frameworks (MOFs), constructed by metal ions or metal clusters and organic ligands through coordination bonds. Post-synthetic modifications (PSMs) provide alternative routes for functionalizing MOFs1, and solvent-assisted linker exchange (SALE)2 is one of the PSMs method with the ability of controlling catenation, accessing polymorphs with comparatively high energy, and producing MOFs with longer linkers, mixed linkers, and/or larger cages.3 Herein, SALE was performed on two pillared MOF, [Zn2(oba)2(4-bpdb)]n ·(DMF)2 (TMU-4) and [Zn(oba)(4-bpmb)0.5]n·(DMF)1.5 (TMU-6), for Cr(VI) reduction. An increase in the Brunauer– Emmett–Teller (BET) surface area along with defects in daughter SALE MOFs (TMU-4′ and TMU-6′) in comparison with the parent MOFs (TMU-4 and TMU-6) led to enhancement of their photocatalytic activity in the reduction of Cr(VI).

Keywords:

Pillared metal−organic frameworks (MOF) , Photocatalytic activity , Cr(VI) reduction , Solvent-assisted linker exchange (SALE).