Iron oxide incorporated carbide nanofiber composites for removal of organic pollutants and heavy metals from water
Chang‐Yeon Kim, Soo Hyeon Kim, Ha‐Rim An, Ji‐In Park, Yujin Jang, Jiwon Seo, Hye‐Ran Kim, Byoungchul Son, Yesul Jeong, Beomgyun Jeong, Hyun Uk Lee
Abstract
In this study, to remove environmental pollutants, we used iron oxide incorporated carbide nanofiber (IOC) composites as heterogeneous catalysts for enhanced decomposition performance and heavy metal absorbents. IOCs were synthesized via electrospinning, a promising technique for reliably producing continuous ultrathin nanofibers. The water-vapor-activated IOC (Act-IOC) showed high crystallinity of Fe3O4 nanoparticles and a large surface area (405.2 m2/g). During the water vapor activation process, Fe3C nanoparticles in carbon nanofiber were oxidized, aggregated, and grew from small Fe3C to large Fe3O4 particles. In addition, the meso-/macroporous structures formed improved the surface area, increasing the number of available active sites for catalytic reactivity. We confirmed that increasing the activation time from 1 to 4 h improved the degradation and adsorption efficiencies by causing the crystal growth of Fe3O4 and increasing the surface area. These results indicate that Act-IOC 4 h had the highest photodegradation performance for tetracycline and ciprofloxacin. Moreover, Act-IOC 1 h showed a better affinity for positively charged heavy metal ions (Pb) than other IOCs because of their higher negative charge. Consequently, we verified that an appropriate activation time is critical. These results imply that the Act-IOC composite is highly efficient for pollutant removal.