Highly efficient iodine capture and selective adsorption and removal of cationic dyes by using a copper-based coordination polymer decorated over graphene oxide and carbon nanotubes

This study focuses on synthesizing hybrid nanocomposites (HNCs) through a one-step solvothermal method, combining highly crystalline and evenly dispersed copper-based coordination polymer (Cu-CP), graphene oxide (GO), and carbon nanotubes (CNTs). Extensive characterization using elemental analysis, SEM, TEM, EDX, XRD, FT-IR, Raman spectroscopy, TGA, and crystallographic studies confirm the properties of the nanocomposites, with PXRD investigation supporting their clear crystalline structure. Morphological and elemental studies reveal effective adsorption of copper-benzoic acid-containing Cu-CP onto GO and CNT substrates. The synthesized nanocomposites exhibit superior adsorption capacity for iodine (I 2 ), a model radioactive pollutant, attributed to decreased CP size and larger surface area. The strong affinity for I 2 arises from various interactions, including conjugated π-electron aromatic systems and halogen bonds. Cu-CP, Cu-CP@GO, and Cu-CP@CNT adsorbents efficiently extract toxic iodine from hexane solution, achieving a substantial capture capacity of 347.85 mg/g over 24 h. In the vapor phase, Cu-CP@GO exhibits an even higher capacity (951.52 mg/g within 25 h). Moreover, the application of Cu-CP, Cu-CP@GO, and Cu-CP@CNT in environmental protection showcases their efficacy in removing cationic and anionic dyes, particularly highlighting remarkable cationic dye selectivity through cation-π and π-π interactions. This research underscores the promising potential of these HNCs in addressing environmental challenges and pollutant remediation.