Fe nanoparticle-functionalized ordered mesoporous carbon with tailored mesostructures and their applications in magnetic removal of Ag(i)

Fe nanoparticle-functionalized ordered mesoporous carbon (Fe /OMC) was synthesized using triblock copolymers as templates and through solvent evaporation self-assembly, followed by a carbothermal reduction. Fe /OMC had three microstructures of two-dimensional hexagonal (space group, p6mm, Fe /OMC-1), body centered cubic (Im3̄m, Fe /OMC-2), and face centered cubic (Fm3̄m, Fe /OMC-3) which were controlled by simply adjusting the template. All Fe /OMC displayed paramagnetic characteristics, with a maximum saturation magnetization of 50.1 emu·g . This high magnetization is advantageous for the swift extraction of the adsorbent from the solution following the adsorption process. Fe /OMC was used as an adsorbent for the removal of silver ions (Ag( )) from aqueous solutions, and the adsorption capacity of Fe /OMC-1 was enhanced by the functionalization of Fe . Adsorption property of Fe /OMC-1 was significantly higher than that of Fe /OMC-2 and Fe /OMC-3, indicating that the long and straight ordered pore channels were more favorable for adsorption, and the adsorption capacity of Ag( ) on Fe /OMC-1 was 233 mg·g . The adsorption process exhibited conformity with both the pseudo-second-order kinetic model and the Freundlich model, suggesting that the dominant mechanism of adsorption involved multilayer adsorption on heterogeneous surfaces.