Hierarchically porous polyamidoxime/ZIF-8 hybrid aerogels for efficient uranium extraction

Efficient uranium extraction is critical for ensuring nuclear fuel supply and minimizing environmental risks. Although polyamidoxime (PAO) exhibits strong and selective binding toward uranyl ions, conventional PAO-based materials suffer from limited adsorption efficiency due to suboptimal pore architecture and restricted mass transfer. Herein, we combine the ice-templating technique with an in-situ growth strategy to integrate PAO with ZIF-8, forming hierarchically porous PAO@ZIF-8 aerogels for efficient uranium extraction. The integration of a hierarchical porous architecture and multiple synergistic active sites endows the aerogels with high uranium adsorption capacity of 741.6 mg g −1 in deionized water. The aerogels demonstrate good mechanical strength, hydrophilicity, and thermal stability, ensuring their structural integrity and operational reliability in practical applications. Moreover, the PAO@ZIF-8 aerogels show high selectivity for uranyl ions (UO 2 2+ ), significantly surpassing common competing ions. This superior performance arises from the synergistic effect of amidoxime functional groups and the ZIF-8 framework, which provide abundant coordination sites and rapid mass transfer pathways. With facile synthesis, high efficiency, and superior selectivity, the PAO@ZIF-8 aerogels hold great promise for practical uranium recovery from seawater and remediation of nuclear wastewater, advancing the sustainable development of nuclear energy and environmental protection.