Mesoporous Organic–Inorganic Core–Shell Necklace Cages for Potentially Capturing Cd ²⁺ Ions from Water Sources

Abstract

Abstract We report the one‐pot synthesis of ball‐like nanosphere structures composed of an α‐Fe core and an organic shell of ethylenediaminetetraacetic acid that connected together to form a nanochain necklace‐like morphology. The hierarchical zigzag nanochain sphere structures have branches growing in clumps, a large surface area, and spherical pore‐like cages and entrances for capture/trapping Cd 2+ ions from water sources. The pH solution (i.e., at pH 5) plays a key role in the generation of actively negative surfaces along the entire nanochain sphere adsorbent, thereby creating surfaces with strong binding affinity to Cd 2+ ions. The thermodynamic and kinetic characteristics indicated that the nanochain sphere adsorbent with macro‐ and meso‐cage caves and organically decorated surfaces show promise for the spontaneous and endothermic capturing of Cd 2+ ion containments from water solutions. The zigzag nanochain mesoporous necklace‐like structure trapper (MNT) exhibited long‐term stability, indicating that it can be used several times (reduced waste volume). The adsorption efficiency and uptake of the deleterious Cd 2+ ions retained even after multi‐particulate processing of reuse cycles. The pH‐dependent Cd 2+ ion selectivity indicated high adsorption capacity (526.3 mg⋅g −1 ) and Cd 2+ ion‐to‐MNT binding affinity, despite the addition of interfering cations or anions. The zigzag nanochain sphere necklace allows the development of a simple and effective adsorbent model for water purification and management of toxins.