Photocatalytic Hydrogel Assists Synergistic Antibacterial and Anticorrosive Action

Hydrogels show potential for microbiologically influenced corrosion protection but face limitations from weak mechanical properties and toxicity from chemical crosslinkers. Herein, we prepared a photocatalytic antibacterial hydrogel by using chitosan and sodium alginate with loaded 2D g-C3N4, showing strong tensile properties, low swelling rates and exceptional antibacterial rate against Escherichia coli and Staphylococcus aureus. The adsorption of bacteria by -NH2 and the generation of reactive oxygen species by 2D g-C3N4 are the main reasons for antibacterial activity. Additionally, the electron-rich microenvironment formed by -NH2 and -OH attracts the h+ generated by 2D g-C3N4 photocatalysis, thereby increasing the charge carrier separation efficiency. Density functional theory calculations also support this inference. The inclusion of 2D g-C3N4 nanomaterials changes the hydrogel structure, disrupting hydrogen bonds to expose more -NH2 groups that bind with H+ to enhance active adsorption. This innovative hydrogel presents a novel approach for safeguarding against microbial corrosion in marine settings.