In the present work, the effect of graphene oxide (GO) nanosheets on the antibacterial activity of CuO nanowire arrays under visible light irradiation is shown. A combined thermal oxidation/electrophoretic deposition technique was employed to prepare three-dimensional networks of graphene oxide nanosheets hybridized with vertically aligned CuO nanowires. With the help of standard antibacterial assays and X-ray photoelectron spectroscopy, it is shown that the light-activated antibacterial response of the hybrid material against gram-negative Escherichia coli is significantly improved as the oxide functional groups of the GO nanosheets are reduced. In order to explore the physicochemical mechanism behind this behavior, ab-initio simulations based on density functional theory were performed and the effect of surface functional groups and hybridization were elucidated. Supported by the experiments, a three-step photo-antibacterial based mechanism is suggested: (i) injection of an electron from CuO into rGO, (ii) localization of the excess electron on rGO functional groups, and (iii) release of reactive oxygen species lethal to bacteria. Activation of new photoactive and physical mechanisms in the hybrid system makes rGO-modified CuO nanowire coatings as promising nanostructure devices for antimicrobial applications in particular for dry environments.

在本工作中，显示了在可见光照射下氧化石墨烯（GO）纳米片对CuO纳米线阵列的抗菌活性的影响。采用组合的热氧化/电泳沉积技术来制备与垂直排列的CuO纳米线杂化的氧化石墨烯纳米片的三维网络。借助于标准的抗菌测定和X射线光电子能谱，结果表明，随着GO纳米片的氧化物官能团的减少，杂化材料对革兰氏阴性大肠杆菌的光活化抗菌反应得到了显着改善。为了探索这种行为背后的理化机理，进行了基于密度泛函理论的从头算，并阐明了表面官能团和杂交的影响。在实验的支持下，提出了一种基于三步光抗菌的机理：（i）将电子从CuO注入rGO，（ii）在rGO官能团上定位过量的电子，以及（iii）释放活性氧对细菌具有致命性的物种。混合系统中新的光敏和物理机制的激活使rGO改性的CuO纳米线涂层成为抗微生物应用特别是干燥环境中有希望的纳米结构器件。（ii）过量电子在rGO官能团上的定位，以及（iii）释放对细菌致死的活性氧。混合系统中新的光敏和物理机制的激活使rGO改性的CuO纳米线涂层成为抗微生物应用特别是干燥环境中有希望的纳米结构器件。（ii）过量电子在rGO官能团上的定位，以及（iii）释放对细菌致死的活性氧。混合系统中新的光敏和物理机制的激活使rGO改性的CuO纳米线涂层成为抗微生物应用特别是干燥环境中有希望的纳米结构器件。