Solvothermal synthesis, structures, and gas adsorption properties of two cadmium-organic frameworks

• Two cadmium-organic frameworks were synthesized and structurally characterized.
• We found an in situ reaction in which a new ligand dpmtz was generated.
• Cd(dpmtz)2 shows selective adsorption behavior of CO2 over N2.

Two cadmium-organic frameworks were synthesized, namely, [Cd(dptz)2]·{Cd[(NH2)2CS]4}·(NO3)4 (1, dptz = 3,6-di-(pyridin-4-yl)-1,2,4,5-tetrazine) and Cd(dpmtz)2 (2, dpmtz = 3,6-di-(pyridin-4-yl)-1,2-dihydro-1-mercapto-1,2,4,5-tetrazine). Compound 1 was obtained by the self-assembly of dptz, Cd(SPh)2 and thiourea under solvothermal conditions. Compound 2 was prepared through an in situ ligand reaction in which generated a new ligand dpmtz only by changing reaction temperature. Compound 1 and 2 were characterized by single-crystal X-ray structure determination, thermogravimetric analysis and powder X-ray diffraction studies. The adsorption behavior shows that compound 2 has selective adsorption capacities of CO2 over N2.

By changing the reaction temperature, we synthesize and characterize compound Cd(dpmtz)2 which shows selective adsorption behavior of CO2 over N2.Figure optionsDownload as PowerPoint slide