An Efficient Uranium Adsorption Magnetic Platform Based on Amidoxime-Functionalized Flower-like Fe3O4@TiO2 Core–Shell Microspheres

• Published in: ACS applied materials & interfaces 2021-04, Vol.13 (15), p.17931-17939
• Main Authors: Zhao, Min, Cui, Zhenpeng, Pan, Duoqiang, Fan, Fuyou, Tang, Junhao, Hu, Yameng, Xu, Yang, Zhang, Pengcheng, Li, Ping, Kong, Xiang-Yu, Wu, Wangsuo
• Format: Article
• Language: English
• Subjects: Functional Nanostructured Materials (including low-D carbon)
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.1c00556

Efficient removal of uranium (U) from aqueous solutions is crucial for ecological safety. Functionalized magnetic nanoparticles provide a promising strategy for radionuclide recovery and separation. However, designing and synthesizing magnetic adsorbents with high sorption capacity and selectivity, accompanied by excellent stability and reusability, remain a challenge. In this work, novel amidoxime-functionalized flower-like magnetic Fe3O4@TiO2 core–shell microspheres are designed and synthesized to efficiently remove U­(VI) from aqueous solutions and actual seawater. The magnetic Fe3O4 core facilitates easy separation by an external magnetic field, and flower-like TiO2 nanosheets provide abundant specific surface areas and functionalization sites. The grafted amidoxime (AO) groups could function as a claw for catching uranium. The maximum adsorption capacity on U­(VI) of the designed nanospheres reaches 313.6 mg·g–1 at pH 6.0, and the adsorption efficiency is maintained at 97% after 10 cycles. In addition, the excellent selectivity of the magnetic recyclable AO-functioning Fe3O4@TiO2 microspheres endows the potential of uranium extraction from seawater. The designed material provides an effective and applicable diagram for radioactive element elimination and enrichment.