Promoted Type I and II ROS Generation by a Covalent Organic Framework through Sonosensitization and PMS Activation

Abstract

Reactive oxygen species (ROS) are one of the most useful chemicals in photo-therapeutic and catalytic applications. In order to effectively generate ROS, the role of light-absorbing photosensitizers or activators for pre-ROS sources like peroxymonosulfate (PMS) is significantly essential. Although metal-based ROS-generating materials have been widely utilized due to the affordable heavy atom effect or viable catalytic sites, the potential toxicity of leached metal ions can be sometimes an undesirable hazard to humans and ecosystems. Herein, we prepare a covalent organic framework (COF) that generates both type I and II ROS upon ultrasound irradiation. In addition, the COF effectively generated ROS through PMS activation even without light sources or catalytic metal sites. We also observed synergistic ROS generation by sonosensitization and PMS activation by the COF. This work is a demonstration of the COF material functioning as both a sonosensitizer and a PMS activator.