A functional cobalt-organic framework constructed by triphenylamine tricarboxylate: Detect nitroaromatics by fluorescence sensing and UV-shielding

Abstract

Luminescent metal-organic frameworks (LMOF) with ligand-modified are a promising strategy to be applied to fabricate chemical sensors. Herein, a novel Co (II) metal-organic framework (Co-MOF), namely Co [(NTB) bpy] (NTB = 4,4′4″-tricarboxylic acid triphenylamine, bpy = 4,4 ′-bipyridyl), was successfully synthesized with excellent water stability and fluorescence properties. Due to the propeller structure of NTB ligands, a special topological structure of Co-MOF was shown: {24.416.68}{2}4. It was proved that Co-MOF has great stability by soaking in different solvents for two weeks. Remarkably, the fluorescence quenching experiment verified that Co-MOF has excellent fluorescence sensor performance. Trinitrophenol, 2,4-dinitrophenol, and 2-amino-4-nitrotoluene (10−5 M) with LOD of 9.00 × 10−5, 5.40 × 10−5 and 5.07 × 10−6 M can be detected via the process of fluorescence enhancement and quenching. Throughout the investigation, the mechanics of fluorescence quenching was performed. Due to the excellent UV absorption capacity of Co-MOF, it was a promising application to combine low-dimensional nanomaterials with sustainable biomass materials. A hybrid films of Co-MOF and cellulose acetate (CA) was generated. The hybrid films had highly transparency in the visible wavelength range and excellent UV-shielding ability owing to the CA/Co-MOF hybrid films enhanced the UV absorption capacity of Co-MOF.