Spatial Confinement of Co Nanoparticles in N-Doped Carbon Nanorods for Wastewater Purification via CaSO₃ Activation

Abstract

Spatial confinement of organic pollutants and reactive oxygen species (e.g., SO 4•− and • OH) with ultrashort lifetime inside the scale of chemical theoretical diffusion could provide a greatly promising strategy to overcome the limitation of mass transfer in the heterogeneous Fenton-like oxidation process. Herein, we first reported spatial confinement of cobalt nanoparticles in N-doped carbon nanorods (Co-NCNRs), by encapsulating Co nanoparticles into Ndoped carbon nanorods, in activating CaSO 3 for antibiotic degradation. Compared to Na 2 SO 3 and NaHSO 3 , CaSO 3 could slowly and persistently discharge SO 3 2− due to its low solubility, thus avoiding the depletion of the generated SO 3•− and • OH under the high concentration of sulfite ions. Fully physical characterizations confirmed that the 3D hydrogel was mostly transformed into the nanorod structure of Co-NCNRs at 550 °C. Co atoms were successfully nanoconfined into N-doped carbon nanorods, which contributes to mass transfer and prevents the agglomeration of Co nanoparticles, thus enhancing its catalytic activity and stability in activating CaSO 3 for water decontamination. The catalytic performance, kinetic research, influences of inorganic anions, pH, and degradation mechanism of chlortetracycline degradation catalyzed by the Co-NCNRs/CaSO 3 system have been studied in detail. This work not only proposed a facile method for synthesis of nanoconfined catalyst but also provided an excellent Co-NCNRs/ CaSO 3 system for wastewater treatment.

Peracetic Acid Activation by Modified Hematite for Water Purification: Performance, Degradation Pathways, and Mechanism

“…Due to the widespread use of antibiotics around the world, more and more antibiotics are entering the ecological environment through various pathways, resulting in higher concentrations of residual antibiotics in the environment. − Cefazolin (CFZ), as a typical β-lactamide antibiotic, is usually recommended for preventing postoperative infections . Due to its nondegradable nature in the natural environment, CFZ can easily accumulate in soil and water resources, causing significant impacts on the ecological environment. − Therefore, there is an urgent need for a practical and feasible method to eliminate these pollutants.…”