▎ 摘　　要

The phototransformation and environmental implications of graphene oxide (GO) have been widely studied in order to understand its implications upon release into the environment. However, very little is known about the formation of reactive oxygen species (ROS) by GO under solar irradiation. Currently there are no studies on the mechanism of ROS formation by GO or the amount of ROS catalyzed by the nanomaterials in the environment. In this study, we carefully investigated the different types and formation mechanisms of ROS generated by GO in the presence of simulated solar irradiation. The effect of GO's photoactivity on bisphenol A (BPA), a representative organic co-pollutant, was also studied. The conduction band electron (e(aq)(-)) of GO led to the formation of different ROS including (OH)-O-center dot, O-2(center dot-), and O-1(2). Among the three types of ROS investigated, O-2(center dot-) was the most abundant species generated during simulated solar irradiation of GO. BPA was degraded, mainly due to the oxidative potential of the valence band holes produced during solar irradiation of GO. This study advances understanding of the photo activity of GO and its potential impact on other possible environmental co-pollutants. (C) 2017 Elsevier Ltd. All rights reserved.