Effect of Electrodeposition Methods of Cuprous Oxide on Antibacterial Properties of Concrete

Three types of electrodeposition, DC electrodeposition, low-frequency pulsed electrodeposition and high-frequency pulsed electrodeposition, were used to deposit cuprous oxide on the concrete surface to improve the antibacterial properties of concrete. The effects of pulse deposition frequency on the antibacterial property of concrete were studied using sulfate-reducing bacteria (SRB) and Escherichia coli (E. coli) as model bacteria. The bacterial concentration and the antibacterial rate were measured to evaluate the antibacterial performance of concrete. The effects of different deposition methods on the elemental content of copper and the amount of copper ions exuded were studied. XRD and SEM were used to analyze the microstructure of the deposited layers. The experimental results show that the concrete treated by electrodeposition exhibited good antibacterial properties against SRB and E. coli. The antibacterial effect of cuprous oxide deposited on concrete by pulse method was better than that by direct current (DC) method. The antibacterial rate of concrete was positively correlated with the exudation rate of copper ion. As the pulse frequency increased, the deposits content on the surface was increased with an accompanying improvement in the antibacterial property. Besides, the pulsed current had an indiscernible effect on the composition of the sediments, which were all mainly composed of Cu2O, but the morphology of the Cu2O differed greatly. Cubic octahedral cuprous oxide had better antibacterial properties with the highest copper ion leaching rate compared with cubic and spherical cuprous oxide.