Interfacial growth of metal-organic framework on carboxyl-functionalized carbon nanotubes for efficient dye adsorption and separation

Hybrid nanocomposites based on UiO-66-NH(2)and carboxyl-functionalized carbon nanotubes were developed in this studyviadifferent synthetic pathways. Combining them through interfacialin situgrowth was beneficial for the better dispersity of UiO-66-NH(2)in the CNTs@UiO-66-NH(2)composite than physically mixing CNTs/UiO-66-NH(2)and chemically bonded CNTs-CONH-UiO-66. Coordination between carboxyl groups of CNTs and zirconium ions resulted in the interfacial growth of UiO-66-NH(2)on CNTs. Adsorption experiments showed that CNTs@UiO-66-NH(2)exhibited the highest adsorption efficiency towards methyl orange (MO). The adsorption capacity of CNTs@UiO-66-NH(2)was up to 392 mg g(-1), which was 77.45% and 201.5% higher than those of CNTs-CONH-UiO-66 and CNTs/UiO-66-NH(2)respectively. Moreover, CNTs@UiO-66-NH(2)could selectively adsorb MO from the MO/MB mixture.