Novel metal–organic frameworks with high stability for selectively sensing nitroaromatics

Abstract

The stability and functionality of metal–organic frameworks (MOFs) are particularly important in considering their potential and/or practical use. Herein we report two novel aldehyde functional group-containing MOFs [Zn₂(L)(BDC)₂]·2DMF·MeOH·H₂O (1) and [Co₂(L)(BDC)₂]·2DMF·2MeOH·H₂O (2) (DMF = N,N-dimethylformamide, MeOH = methanol) achieved by reactions of mixed organic ligands of 2,4-bis[(pyridin-4-yl)methoxy]benzaldehyde (L) and 1,4-benzenedicarboxylic acid (H₂BDC) with the corresponding metal salts under solvothermal conditions. Both 1 and 2 are 2-fold interpenetrated three-dimensional (3D) frameworks. Particularly, 1 exhibits excellent water and wide-range pH stability, and a large Q_st value for carbon dioxide (CO₂) adsorption. Furthermore, photoluminescence (PL) studies indicate that 1 could be considered as a potential luminescent probe for detection of nitroaromatics.