Mimicking ascorbic acid oxidase-like catalysis over adjacent dicopper centers

Abstract

Developing an efficient ascorbic acid oxidase (AAO)-mimicking nanozyme was crucial for its potential applications, but remains challenging. Herein, we found that a nanozyme with adjacent dicopper centers acted as a mimetic of AAO. The non-bonded Cu⋯Cu distance in this nanozyme approached that in AAO, which endowed it with efficient catalytic activity confirmed by a lower K_m and a larger V_max, superior to most of the reported AAO-mimicking artificial enzymes and nanozymes. During 4e catalysis, O₂ was preferentially activated at the Cu centers to generate O₂˙⁻, which was reduced to form H₂O₂ as an intermediate and H₂O as the final product.