Near-infrared light photocatalysis and photothermy of carbon quantum dots and au nanoparticles loaded titania nanotube array

Abstract

The excellent photocatalysis is quite important for coating materials on implants, which can be photoinspired to kill bacteria by locally producing the reactive oxygen species (ROS) within a very short time. Herein, we developed a novel photocatalytic system of Au nanoparticles and carbon quantum dots loaded TiO2 nanotube array (TNTs/Au/CDs) on the surface of titanium. This system can exhibit enhanced near-infrared (NIR) light photocatalysis and photothermy because CDs can convert NIR light into the light of 500–600 nm and transfer electrons, which can inspire nano Au-catalyzed TNTs to generate ROS and enhance the surface plasmon resonance (SPR) effect of Au nanoparticles to produce more local photothermy. The enhanced photocatalysis and local photothermy can exhibit a synergistic effect to kill the bacteria highly effectively within a very short time by damaging the membranes of the bacteria. The antibacterial efficiency of the modified surface is 96.19% and 99.89% against Staphylococcus aureus and Escherichia coli, respectively, under 808 nm NIR light irradiation for 15 min.