Photoelectrocatalytic bacterial inactivation of Acinetobacter baumannii on Cu2O/TiO2@Cu mesh photoanodes

A hybrid Cu2O/TiO2 composite loaded on a Cu mesh (Cu2O/TiO2@Cu mesh) was developed via a supercritical solvothermal route. A uniformly distributed Cu2O/TiO2 p–n hetero-junction was stably coated on a Cu mesh, benefiting the visible-light harvesting. In comparison to electrochemistry and visible-light photocatalysis, the photoelectrochemistry process on the photoanode of the Cu2O/TiO2@Cu mesh presented improved bacterial inactivation activity for Acinetobacter baumannii. By means of the main active species of ˙O2− radicals, the photoelectrocatalytic process on the Cu2O/TiO2@Cu mesh also realized complete leakage of K+ ions, much stronger mineralization of the cell membrane and more efficient elimination of the self-recovery function, finally leading to cell death. In comparison, the electrochemistry process only led to the leakage of K+ ions without inactivation of bacteria, and the visible-light photocatalysis process induced partial leakage of K+ ions and cell mineralization after the death of most bacteria.