Emerging trace organic contaminants (TrOCs) in aquatic environments, characterized by high toxicity, persistence, and bioaccumulation, present major challenges for conventional water treatment technologies. While reactive oxygen species (ROS)-driven advanced oxidation processes (AOPs) hold great promise for TrOCs remediation, challenges persist in achieving efficient, sustainable, and scalable treatment. This review systematically compares ROS generation pathways and addresses associated in situ challenges. It elucidates the relationship between the electronic structures of catalysts and specific ROS production mechanisms. Furthermore, the impact of real water matrix components on both ROS generation and TrOCs degradation pathway is addressed. Our analysis highlights that an integrated approach is essential for overcoming existing limitations, enhancing degradation efficiency, and mitigating risks associated with traditional oxidant storage. We stress the urgent need for comprehensive mechanistic elucidation, robust technological integration, and thorough risk assessment to accelerate the transition of these in situ ROS technologies from laboratory research to widespread, industrial-scale environmental applications.
Yue et al. (2026) studied this question.