Microporous Cd(II) Metal–Organic Framework for CO₂ Catalysis, Luminescent Sensing, and Absorption of Methyl Green

A new porous metal–organic framework (MOF) {[Cd­(Hbptc)]·H₂O}_n (Cdbptc) was assembled by Cd­(II) ions and a rigid (1,1′-biphenyl)-2,4,6-tricarboxylic acid (H₃bptc) ligand via a solvothermal method. Cdbptc was studied by the physical and chemical analyses methods, exhibiting captivating three-dimensional (3D) microporosity with a 1D channel of 1.7 nm decorated by the uncoordinated hydroxyl groups. It is worth noting that clusters were formed by Cd­(II) ions as the Lewis active sites, making it as an excellent reused homogeneous catalyst for the CO₂ cycloaddition reaction. In addition, the fluorescence study of Cdbptc indicated Cr³⁺, Cu²⁺, Fe³⁺, [Fe­(CN)₆]^3–, and Cr₂O₇^2– ions could be multiply detected with a low detection limit. Besides, the dye adsorption experiment demonstrated that methyl green (MG) dye could be selectively adsorbed by Cdbptc from other dyes, and the adsorption mechanism was testified by X-ray photoelectron spectroscopic data and Fourier transform infrared spectrum data.