Synthesis and Structure of a Copper-Based Functional Network for Efficient Organic Dye Adsorption.

In the work, by incorporating polyoxometalates (POMs) into a copper(II)-based network, a novel three-dimensional (3D) porous framework, [Cu 17 Cl 3 (trz) 12 ]H 3 [GaW 12 O 40 ]·9H 2 O ( Cu-GaW-TRZ ), was successfully prepared and explored for the adsorption of dyes. The adsorption capacity of Cu-GaW-TRZ was calculated as 13.11 mg/g, and the dye adsorption rate equaled 96.2% for the adsorption of methylene blue (MB). Furthermore, this recyclable adsorbent is stable enough without obvious loss of adsorption capacity for at least five runs. Meanwhile, the structure of the macropores is suitable for the entry of large molecular dyes, and [GaW 12 O 40 ] 5- also can achieve efficient adsorption for cationic dyes. The results displayed a pseudo-second-order kinetic model and were well matched for MB adsorption onto Cu-GaW-TRZ . The free energy, entropy, and enthalpy of the thermodynamic parameters for the adsorption of MB were calculated, which revealed that the adsorption process was befitting for the adsorption of MB.