Synthesis of Mo-Pt/CeO₂ Dual Single-Atom Nanozyme for Multifunctional Biochemical Detection Applications

Elaborated structural modulation of Pt-based artificial nanozymes can efficiently improve their catalytic activity and expand their applications in clinical diagnosis and biochemical sensing. Herein, a highly efficient dual-site peroxidase mimic composed of highly dispersed Pt and Mo atoms is reported. The obtained Mo-Pt/CeO₂ exhibits exceptional peroxidase-like catalytic activity, with a V_max as high as 34.16 × 10^-8 m s^-1, which is 37.5 times higher than that of the single-site counterpart. Mechanism studies suggest that the Mo atoms can not only serve as adsorption and activation sites for the H₂O₂ substrate but also regulate the charge density of Pt centers to promote the generation ability of •OH. As a result, the synergistic effect between the dual active sites significantly improves the catalytic efficiency. Significantly, the application of the Mo-Pt/CeO₂ catalyst's excellent peroxidase-like activity is extended to various biochemical detection applications, including the trace detection of glucose and cysteine, as well as the assessment of antioxidants' antioxidant capacity. This work reveals the great potential of rational design dual-site active centers for constructing high-performance artificial nanozymes.