Preparation of h-BN@ZnO composite epoxy coating for improve durability and antibacterial properties of concrete

Abstract

Microbiological corrosion is a significant concern because it causes the deterioration of concrete structures in marine and sewage environments. Based on a hybrid antibacterial strategy, a novel antibacterial coating with h-BN@ZnO as filler was successfully prepared to improve the durability and antibacterial properties of concrete structures in harsh environmental conditions. The properties of h-BN@ZnO were characterized, with a focus on investigating its potential antibacterial mechanisms. Furthermore, three types of composite coatings were prepared by incorporating ZnO, h-BN and h-BN@ZnO as fillers. The microstructure, thermal stability, breathability and antibacterial performance of these composite coatings were thoroughly characterized. Immersion test and pull-off test were conducted to evaluate the effectiveness of these composite coatings in improving the durability of concrete structures. The results demonstrated that h-BN@ZnO exhibited excellent antibacterial activity, primarily attributed to the presence of ZnO. Moreover, the unique structure of ZnO on h-BN sheets contributed to enhancing the dispersion stability of h-BN@ZnO. As filler within the coating, h-BN@ZnO demonstrated significant improvements in antibacterial performance and barrier properties. With 2 wt% h-BN@ZnO, the composite coating achieved an impressive 99 % anti-adhesion rate against Escherichia coli and Staphylococcus aureus. In comparison to pure coatings, this coating demonstrated a 50 % reduction in the penetration depth of sulfate ions. It was also observed that a high content of h-BN@ZnO led to further improvements in the barrier properties and antibacterial adhesion rates of the coating. These findings contribute to understanding the potential of incorporating h-BN@ZnO filler into coatings to improve the durability of concrete structures.