Defect engineering of Cu2-xGaxO/PDINH nanomaterial for significantly improved photocatalytic antibacterial activities

The judicious engineering of defects and microstructure in novel photocatalysts is essential for optimizing their functional properties. This study focuses on the design of copper oxide (Cu2O)-based catalysts employing defect engineering and heterogeneous composition with perylene-3,4,9,10-tetracarboximide (PDINH) to enhance their photocatalytic antibacterial performance. Introducing transition metals such as gallium (Ga) into the Cu2O lattice serves to 1) generate Cu vacancies to accelerate reactive oxygen species (ROS) kinetics, 2) induce a small size effect in Cu2O nanoparticles to amplify photocatalytic activities, and 3) fine-tune electronic characteristics by modulating the electron density near the Fermi level and the d-band center. The defect engineering of doped Ga atoms and the p-n junction construction with PDINH resulted in a notable redshift of the light absorption edge of Cu2O. The optimized Cu2-xGaxO/PDINH (x=0.2) nanomaterials displayed superior photocatalytic antibacterial performance, achieving bacterial inhibition rates greater than 91% against Staphylococcus aureus and Pseudomonas aeruginosa. The nanomaterial also exhibited a large double-layer capacitance, elevated photocurrent density, and substantial ROS production. Cu1.8Ga0.2O/PDINH nanomaterial was a potent candidate for photocatalysis and environmentally friendly antibacterial treatments.