High-Loading Copper Cluster Nanozymes for Enhancing Antioxidant Activity

Abstract

Despite significant advancements having been made in the development of nanozymes, discovering highly active nanozyme candidates remains a formidable challenge. Herein, we propose an innovative cross-coupling strategy to construct a high-loading graphdiyne-supported Cu cluster (Cu-GDY) nanozyme with synergetic interactions between neighboring Cu atoms, which can significantly enhance their ability to scavenge reactive oxygen species (ROS). In our unique system, the formation of the GDY featuring uniformly distributed pores from butadiyne linkages concurs with the anchoring of Cu atoms to effectively prevent the aggregation of low-coordinated Cu atoms into large particles throughout the reaction process. Additionally, density functional theory calculations based on free energy diagrams and electronic structure analysis reveals that intersite communication between metal atoms in Cu-GDY lowers the energy barrier for reactions, thereby facilitating both superoxide dismutase-like and catalase-like activities. As expected, our experimental results show that the Cu-GDY nanozyme can function as a highly efficient antioxidant to eliminate ROS. More importantly, our as-obtained Cu-GDY with exceptional antioxidant activity can be integrated into a cigarette filter system, where it can efficiently scavenge various ROS generated during tobacco combustion. Overall, this study presents an innovative approach for constructing high-loading copper cluster nanozymes and broadens the potential application scope of antioxidant nanozymes.