Abstract:Five (5) (mNBA = m-nitro benzoate, BDC = terephthalate, TTA = thenoyltrifluoroacetone, TPTZ = 2,4,6-tri(2-pyridyl)-1,3,5-triazine) have been synthesized. The single X-ray diffraction reveals that TPTZ is mainly in the trident coordination mode and organic aromatic carboxylic acids are in the multiple coordination modes in the crystals. The composition of solvents, reaction temperature and reactant ratios all affect the composition and structure of the formed crystals. Crystals 1 and 3 belong to triclinic system, while the other three belong to monoclinic system. Among them, Crystal complexes 1 and 3 are coordination polymers. The other three crystals are mononuclear complexes with Ln III ions in the asymmetric environment. Both of the Crystal complexes 1 and 2 show strong luminescence emissions of Eu 3+ . The luminescence lifetimes of the two complexes are 0.761 ms and 0.447 ms, respectively. In addition, their luminescence quantum efficiencies are 25.0% and 16.7%, respectively.

Three crystal complexes were designed and synthesised through the solvothermal method, with Cu 2+ , Zn 2+ , and Cd 2+ ions as the metal centres and 2,4,6‐tri(2‐pyridyl)‐ s ‐triazine (TPTZ) and terephthalate (BDC 2− ) as the ligands. Their compositions were determined to be Cd(TPTZ)Cl 2 (Cd‐MOF), {[Zn(TPTZ)(BDC)] ⋅ 3H 2 O} n (Zn‐MOF), and Cu 2 (PCA) 2 (BDC)(H 2 O) 2 (Cu‐MOF) (PCA − =2‐pyridinium amide), respectively. Cd‐MOF can adsorb 90 % of Congo red (CR) in 10 s at room temperature and atmospheric pressure, and CR removal was complete at 20 s over a wide pH range. The adsorption capacity for CR reached 1440 mg g −1 in 5 min. Selective adsorption was demonstrated in mixed dyes. The adsorption kinetic data agree well with the pseudo‐second‐order kinetic model. The Temkin model was successfully used to evaluate the adsorption isotherms of CR on Cd‐MOF at room temperature, suggesting that adsorption occurs through a hybrid of monolayer and multilayer mechanisms.