Ag@CuO@Cu(OH)₂: A Synergistic Catalyst for H₂O₂ Detection with Peroxidase-Mimic Activity without Interference of O₂

Herein, we present silver nanoparticle anchored on copper oxide and copper hydroxide (Ag@CuO@Cu(OH)₂) by green synthetic approach. Interestingly, as-obtained Ag@CuO@Cu(OH)₂ not only enhances the peroxidase-like activity but also eliminates oxidase-like activity. The peroxidase-like activity was enhanced mainly due to the abundance of Ag⁺ and Cu²⁺ vacant states, which populate reactive oxygen species (ROS). This prolonged peroxidase-like activity of Ag@CuO@Cu(OH)₂ was successfully recognized H₂O₂ and also have long stability and repeatability. The proposed strategy, finding nanozymes with single activity will open a new opportunity to enhance the performance of colorimetric sensors.