A luminescent Zr-based metal–organic framework for sensing/capture of nitrobenzene and high-pressure separation of CH4/C2H6

Abstract

We present a novel luminescent metal–organic framework (LMOF) based on zirconium metal oxide cluster Zr₆O₈ bonding with a new tetratopic linker 1,3,6,8-tetrakis(4′-carboxy[1,1′-biphenyl]-4-yl-)pyrene. This (4,12)-connected ftw-a-type net is composed of a large solvent-accessible volume of 79.5% volume per unit cell with a BET surface area up to 3540.5 m² g⁻¹. The activated LMOF exhibits an unprecedented fluorescence quenching effect triggered by nitrobenzene (NB) with quench percentage up to 99.5%, and could reversibly take up 14.7 mmol g⁻¹ of NB under atmospheric conditions. The breakthrough curve of CH₄ and C₂H₆ at 298 K and 2.0 MPa demonstrates that the activated LMOF has high-performance selective adsorption for CH₄ with a selectivity of 25.45, which is an unusually high value as compared with those of reported materials.