Coordination of Mg(II) Enhancing Photoinduced Oxidase-Like Activity of Carbon Dots for Efficient Degradation of Organic Dyes
Jinyu Shi, Jing Li, Xuemin Li, Yuxin Zhang, Jiao Hu, Yu Ning, Chuan‐Hua Zhou, Zhining Xia, Cui Liu
Abstract
Water pollution caused by organic dyes not only seriously damages the ecological environment but also poses a great threat to human health. Herein, the doping of Mg(II) enhancing the photoinduced oxidase-like activity of carbon dots (CDs) in a wide pH range from 2.3 to 8.2 is reported. The Mg-CDs catalyze the generation of superoxide anions (O 2 •– ) and singlet oxygen ( 1 O 2 ) from dissolved oxygen under light irradiation. Compared to CDs without Mg(II) doping, Mg-CDs exhibit much higher photoinduced oxidase-like activity (more than 250%) because the coordination of Mg(II) facilitates the content ratio of enol to ketone, enhancing the rigidity of the π-system and boosting the electron transition within CDs. A universal strategy for degrading organic dyes, including azo, triphenylmethane alkaline, and alkaline azo dyes, is constructed based on the remarkable photoinduced oxidase-like performance of Mg-CDs. The degradation rates of methyl orange, crystal violet, and rhodamine B are 92.2%, 96.5%, and 98.5%, respectively. Our findings provide a strategy to design desirable photoinduced nanozymes for water pollution control and demonstrate great potential of metal-doped CDs in photocatalysis.