Iodine-doped single-atom cobalt catalysts with boosted antioxidant enzyme-like activity for colitis therapy

Doping with heteroatoms was performed as an effective strategy for modulating the electronic structure of single metal atom and further enhancing the catalytic activity of single-atom catalysts (SACs). Single-atom cobalt catalysts anchored on nitrogen-doped carbon (CoCN) have achieved considerable attention in biosensors and anti-inflammation therapy. How to further improve the antioxidant activity of CoCN for satisfying their biomedical applications is a hot topic. Here, we synthesized a series of halogen-doped CoCN, obtained CoCNF, CoCNCl, CoCNBr and CoCNI. We found the catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) -like catalytic activities of CoCNCl, CoCNBr and CoCNI significantly increased than that of CoCN. Especially, CoCNI exhibited the highest antioxidant capacity. Finally, we used CoCNI as the remarkable reactive oxygen species (ROS) eliminating material in protecting cellular against oxidase stress in vitro and colitis therapy in vivo. Our work opens a new insight to design SACs with high catalytic activities by halogen doping for ROS-relative disease therapy.