Two novel lanthanide metal–organic frameworks based on tetraphenylethylene for ultra-high proton conduction

Abstract

Two novel isostructural anionic lanthanide metal–organic frameworks, (Me₂NH₂)[Ln(HTCBPE-F)·(HCOO)·DMF]·4.5DMF·2H₂O (Eu-MOF and Dy-MOF), based on tetraphenylethylene carboxylate ligands were successfully constructed and characterized. These two MOFs possess porous structures and water stabilities with uncoordinated carboxylate groups and dimethyl ammonium cations, which allow for high proton conductivities (5.35 × 10⁻² and 1.22 × 10⁻² S cm⁻¹) at 98% RH (relative humidity) and 90 °C. Based on the structural characteristics and activation energy, the proton transfer mechanism is proposed.