Bell-shaped magnetic hollow porous carbon: an efficient and sustainably recycled iodine absorbent in aqueous solution

Abstract

Given the threat of radioactive iodine (RI) to the environment and human health, developing highly efficient and easily recoverable iodine absorbents in water is still a challenge in practical applications. Herein, a novel porous magnetic carbon material was successfully prepared by annealing in situ polymerized dopamine on an Fe₂O₃ template, and hollow porous carbon (H-PC) and bell-shaped magnetic porous carbon (BM-PC) can be controllably obtained by completely or partially removing Fe₃O₄ generated during annealing. Interestingly, H-PC exhibits outstanding iodine adsorption performance in water with a higher capacity of 945.97 mg g⁻¹ due to its special hollow porous structure, which can not only increase the active sites in the absorbent but also effectively accelerate mass transfer through its inner and outer surfaces. Moreover, the synthesized BM-PC with good magnetism can be easily recycled from solution, which has been proven with excellent stability and reusability for iodine adsorption and recovery in water, indicating its promising practical potential. Therefore, this research not only provides a novel perspective for effective treatment of RI pollution but also opens a new way for the sustainable recycling and practical utilization of absorbents.