Proton‐Functionalized Graphitic Carbon Nitride for Efficient Metal‐Free Destruction of Escherichia coli under Low‐Power Light Irradiation

Universal access to clean water has been a global ambition over the years. Photocatalytic water disinfection through advanced oxidation processes has been regarded as one of the promising methods for breaking down microbials. The forefront of this research focuses on the application of metal‐free photocatalysts for disinfection to prevent secondary pollution. Graphitic carbon nitride (g‐C3N4) has achieved instant attention as a metal‐free and visible‐light‐responsive photocatalyst for various energy and environmental applications. However, the photocatalytic efficiency of g‐C3N4 is still affected by its rapid charge recombination and sluggish electron‐transfer kinetics. In this contribution, two‐dimensionally protonated g‐C3N4 was employed as metal‐free photocatalyst for water treatment and demonstrated 100 % of Escherichia coli within 4 h under irradiation with a 23 W light bulb. The introduction of protonation can modulate the surface charge of g‐C3N4; this enhances its conductivity and provides a “highway” for the delocalization of electrons. This work highlights the potential of conjugated polymers in antibacterial application. Water, water everywhere: The efficiency of graphitic carbon nitride (g‐C3N4) in photocatalytic water disinfection is plagued by its rapid charge recombination and sluggish electron‐transfer kinetics. Protonation of g‐C3N4 can enhance its conductivity and provide a “highway” for the delocalization of electrons. Consequently, protonated g‐C3N4 demonstrated 100 % destruction of E. coli within 4 h under low‐power household light irradiation.