Electrophoresis-Deposited Mesoporous Graphitic Carbon Nitride Surfaces with Efficient Bactericidal Properties

With the rise of bacterial infections and antimicrobial resistance, it is important to develop environmentally friendly functional materials and surfaces with efficient bactericidal activity. In this work, nanostructured graphitic carbon nitride (g-C₃N₄) surfaces were fabricated by electrophoresis deposition of mesoporous g-C₃N₄ materials. Efficient bactericidal performance was achieved through the synergistic biophysical interaction of bacterial cells with the nanotopographies and visible light active photocatalytic properties. The nanotopographies of g-C₃N₄ surfaces demonstrated a “contact-killing” efficiency of >90% against Pseudomonas aeruginosa and >80% against Staphylococcus aureus cells. The number of surviving bacteria on the surfaces further decreased remarkably upon illumination using visible light generated by a light-emitting diode lamp with an irradiation intensity of 12.4 mW cm^–2. In total, the number of viable bacteria was reduced by approximately 3 orders of magnitude for P. aeruginosa and 2 orders of magnitude for S. aureus. Our experimental findings provide potential prospects for developing highly efficient photocatalytic bactericidal surfaces.