Using C-Doping to Identify Photocatalytic Properties of Graphitic Carbon Nitride That Govern Antibacterial Efficacy
Graphitic carbon nitride (g-C3N4) is a promising photocatalyst for bacterial disinfection. Herein, carbon doping (C-doping) was employed to manipulate g-C3N4 physicochemical properties and demonstrate a potential avenue toward rationally designing g-C3N4 for improved antibacterial efficacy. Six g-C3N4 samples were prepared by thermal condensation with increasing amounts of barbituric acid (5-50% C-doping) and varying pyrolysis temperatures (550 and 600 °C). Relationships among the synthesis approach, the resulting physicochemical properties, and the efficacy for bacterial inactivation are identified. C-Doping was found to decrease the Escherichia coli (E. coli) K12 inactivation rate, and the g-C3N4 synthesized at 550 °C (base sample) was found to have the best photocatalytic performance. The results indicate significant E. coli inactivation with 5% and 15% C-doped samples, revealing that C-doping is an effective avenue for expanding the visible-light range of absorption while inducing disinfection. In addition, the base sample is effective against clinically and environmentally relevant antibiotic-resistant pathogens, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycinresistant Enterococcus faecalis (VRE).
