Abstract
Peroxidase (POD)-like nanozymes are attracting increasing attention in anti-tumor, antibacterial, disease diagnosis, and environmental applications. However, simultaneously improving the POD-like activity and stability of nanozymes remains a non-trivial challenge. Inspired by the excellent stability and multiple active sites of high-entropy alloys, we design a Ru-based (RuPtIrRhCu) high-entropy alloy nanozyme (HEAzyme) with improved catalytic activity and stability. Benefiting from the strong adsorption capacity of Ru toward hydrogen peroxide (H(2)O(2))/hydroxyl (OH) and the collaborative effect induced by the multiple elements, an interesting "hydroxyl spillover" route is triggered on the RuPtIrRhCu HEAzymes. The efficient dissociated adsorption of H(2)O(2) and fast transfer of adsorbed hydroxyl (*OH, * denotes the adsorbed state) is achieved, resulting in boosted POD-like activity. The POD-like activity of the HEAzyme remained unchanged for 6 months, exhibiting outstanding stability. A multi-channel colorimetric sensor array was developed to specifically identify eight biological antioxidants, especially for the chiral recognition of l-cysteine (l-Cys) and d-cysteine (d-Cys). This study not only provides an effective, multi-site collaborative mechanism for improving POD-like activity and stability but also extends the horizons and perspectives in nanozymes.