Fabrication of CuO/BiVO₄ composites for enhanced visible-light-driven photocatalytic antibacterial activity

In recent years, photocatalytic antibacterial technology has attracted wide attention due to its advantages of broad-spectrum antibacterial activity, high stability, safety and non-toxicity. Bismuth vanadate (BiVO₄) reveals a strong response to visible light, however, the photocatalytic activity of pure BiVO₄ remains unsatisfactory. In the present work, CuO/BiVO₄ composites were successfully constructed, and the photocatalytic performance and antibacterial mechanism were systematically studied. The antibacterial results confirmed that the CuO/BiVO₄ composites exhibited enhanced photocatalytic antibacterial activity against Escherichia coli (E. coli). With the CuO addition of 12.5%, the CuO/BiVO₄ composites presented superior antibacterial performance, and the antibacterial rate reached 100% under visible light irradiation for 30 min, while the antibacterial rate for BiVO₄ was less than 20% under the same conditions. In addition, CuO/BiVO₄ composites displayed a long-term effect, and the antibacterial rate was kept at >90% after 5 cycles. The antibacterial mechanism was mainly from ROS oxidative damage, in which ·O₂ ^- played a major role in antibacterial activity.