Dual‐Site Trigger Electronic Communication Effects to Accelerate H₂O₂ Activation for Colorimetric Sensing of Uranyl Ions in Seawater

Abstract Efficient activation of hydrogen peroxide (H₂O₂) through biomimetic catalysis still faces a major challenge. In this work, inspired by the catalytic pocket of natural peroxidase, Cu single atom (Cu_SA) and AuCu nanoparticles (AuCu_NPs) anchored on nitrogen‐doped carbon skeleton (Cu_SA‐AuCu_NPs/NC) serve as dual active sites that significantly accelerate the charge transfer process and thus achieve efficient H₂O₂ activation. Meanwhile, the experimental and theoretical calculations show that the well‐established electronic communication effect between Cu_SA and AuCu_NPs results in moderate electronic modifications to Cu_SA, which promotes the heterolysis of H₂O₂ and the timely desorption of H₂O. As a proof of concept, Cu_SA‐AuCu_NPs/NC show remarkable performance in detecting uranyl ions in seawater. This work provides new insights into the H₂O₂ activation for colorimetric sensing.