Visible‐light‐driven photocatalytic degradation of antibiotics by newly molding g‐C3N4/graphitized biochar composites

• Published in: ChemistrySelect (Weinheim) 2023-07, Vol.8 (25), p.n/a
• Main Authors: Chen, Hanyu, Fang, Yanying, Duan, Peiyu, Zhang, Xueqi, Zhang, Kunfeng
• Format: Article
• Language: English
• Subjects: Biochar; g-C3N4; Photocatalytic; Sunflower seed shells
• ISSN: 2365-6549; 2365-6549
• DOI: 10.1002/slct.202300658

Newly molding g‐C3N4/graphitized biochar (g‐C3N4/GSBC) molding composites photocatalytic material with superior photocatalytic activity were successfully synthesized by the impregnation‐roasting process. The photocatalytic behavior of g‐C3N4/GSBC was assessed in the photocatalytic degradation of antibiotic pollutants, including sulfamethoxazole(SMZ), ciprofloxacin(CIP), and tetracycline(TC), under visible light illumination. The successful composited of g‐C3N4 with GSBC was demonstrated by various characterization results, in which the 5 : 1 mass loading ratio showed the best performance. g‐C3N4/GSBC possessed a larger specific surface area (71.09 m2/g), suitable band gap (2.66 eV), more catalytically active species, and higher utilization efficiency of visible light than powdered g‐C3N4. The removal efficiency of the new composite was higher than that of g‐C3N4 for the three antibiotics, with removal efficiencies of 87.2 %, 83.2 %, and 72.2 % for SMZ, TC, and CIP, respectively. The analysis of its photodegradation mechanism revealed that h+ and ⋅O2− are responsible for the antibiotics′ decomposition. According to the HPLC‐MS results, the possible photocatalytic mechanism and reaction pathways have been proposed. This work provided a new way for the synthesis of molding photocatalysts as an efficient photocatalyst for the degradation of organic contaminants. Newly molding g‐C3N4/graphitized biochar (g‐C3N4/GSBC) molding composites photocatalytic material with superior photocatalytic activity were successfully synthesized by the impregnation‐roasting process. The properties of g‐C3N4/GSBC composites, namely the catalytic, optical property, and absorption capacity, were obviously improved by combining GSBC and g‐C3N4. The g‐C3N4/GSBC 5 : 1 composite exhibits supreme photocatalysis performance on the degradation under light irradiation. The mechanism of improving activity is due to the coupling of biochar and g‐C3N4, which leads to an expanded layer spacing and can effectively enhance charge transfer. This study of the g‐C3N4/GSBC photocatalytic composites prepared from sunflower seed shells not only realized the reuse of biological waste but also achieved the effective removal of antibiotics from water and provided a new concept and path for the development of organic pollutant purification technology.