Graphitic carbon nitride loaded with bismuth nanoparticles displays antibacterial photocatalytic activity

Metal-free graphitic carbon nitride nanomaterials have been widely applied in the medical antibacterial field owing to their high anisotropy, excellent stability,satisfactory biocompatibility, and non-toxicity. Herein, Bi/C_(3)N_(4) nanocomposites were successfully constructed by hydrothermal method followed by loading bismuth on the surface of graphite carbon nitride. Bi nanospheres were tightly combined with the layered g-C_(3)N_(4) surface to promote effective separation of photo-induced charges, which results in the Bi/C_(3)N_(4) composite material that exhibited excellent photocatalytic activity under visible light. In addition, the surface plasmon resonance characteristics of semi-metal Bi further enhanced the visible-light absorption of the Bi/C_(3)N_(4). However, excessive Bi may inhibit the light-trapping ability of Bi/C_(3)N_(4).1.0% Bi/C_(3)N_(4) demonstrates excellent bactericidal efficiency as high as 96.4% against Escherichia coli(E. coli), which is attributed to the promotion of the production of reactive oxidative species.The enhanced mechanism of Bi/C_(3)N_(4) synergistically achieving enhanced photocatalytic antibacterial activity under the coupling of multiple advantages was clarified,providing theoretical guidance for its application in the field of water disinfection and antibacterial treatment.