A Novel MultifunctionalCd-MOF Containing Thiazolo[5,4‑<i>d</i>]thiazoleand Azo Moieties for Highly Efficient Adsorptionof Iodine and Catalytic CO₂ Cycloaddition

A novel complex, {[Cd(NO₃)(4,4′-Azo)_0.5(DPTzTz)]·DMF}_<i>n</i> (MOF-<b>1</b>), was obtained by assembling photoactive ligand 2,5-di(pyridin-4-yl)thiazolo[5,4-<i>d</i>]thiazole (DPTzTz) and azo-functionalized dicarboxylic acid linker (4,4′-azodibenzoic acid = 4,4′- H₂Azo) under solvothermal conditions. MOF-<b>1</b> bears a 2-fold interpenetrated 3D framework with 1D open channels. The channel wall was decorated with Lewis acidic Cd(II) center and Lewis basic groups (NN, TzTz). The title complex exhibited excellent thermal stability and robust chemical stability. After activation, the sample (MOF-<b>1a</b>) can act as a heterogeneous catalyst for the CO₂ cycloaddition reaction under mild conditions. Moreover, it can encapsulate 680.1 mg·g^–1 and 737.2 mg·g^–1 iodine in the vapor phase and in cyclohexane solution (320 mg·L^–1), respectively. MOF-<b>1a</b> shows easy recovery and reuse without an obvious decrease of catalytic activity and adsorption capacity. Therefore, MOF-<b>1</b> is a multifunctional and stable material for iodine adsorption and catalytic CO₂ cycloaddition.