Three-Dimensional Porous Heterometallic-Organic Frameworks: Synthesis, Luminescent, Magnetic, Adsorption and Hydrogen Storage Properties

Abstract

Two three-dimensional (3D) porous heterometal-organic frameworks (HMOFs) with isostructures, [Zn2Cd(OH)(BTC)2(DMF)(H2O)2]·(H3O) (JUC-155A) and [ZnCo2(OH)(BTC)2(DMF)(H2O)2]·(H3O) (JUC-155B) (JUC=Jilin University China, BTC=1,3,5-benzenetricarboxylate and DMF=N,N-dimethylformamide), have been successfully synthesized by utilizing two kinds of 3d metal ions (Zn(II) and Cd(II) or Zn(II) and Co(II)) under conformable conditions. X-ray crystallography reveals that both HMOFs consist of trinuclear metal-carboxylate secondary building units (SBUs), and these SBUs are interlinked by the phenyl groups of BTC ligands to generate 3D open-frameworks with two types of channels of about 6.3 and 10.7 Å. Both HMOFs show the multifunctional properties in photoluminescence and adsorption. JUC-155B also exhibits an antiferromagnetic interaction, owing to the presence of dinuclear cobalt centers. Additionally, the high-pressure hydrogen storage of JUC-155A has been also examined at 77 K. By using mixed metal centers in clustered SBUs, it is a good strategy to construct those isostructures with heterometallic systems, and it is believed that the presence of such HMOFs will further facilitate the exploration of multifunctional materials.