Ultra-sensitive H₂O₂ sensing with 3-D porous Au/CuO/Pt hybrid framework

A 3-D porous Au/CuO/Pt hybrid platform is proposed to overcome the drawbacks of non-enzymatic H₂O₂ sensing. The Au/CuO/Pt hybrid sensor exhibits an extraordinary catalytic performance towards H₂O₂ reduction with an ultra-high sensitivity of 25,836 µA mM⁻¹ cm⁻² and a limit of detection of 1.8 nM (S/N = 3). It demonstrates an excellent anti-interference ability for NaCl, fructose, ascorbic acid, citric acid, dopamine, and glucose. The hybrid Au/CuO/Pt sensor exhibits outstanding stability for a wide range of molarity applications as well as a stable current for a long period of 30 h. These rank the proposed Au/CuO/Pt framework as one of the best-performing non-enzymatic H₂O₂ sensors. The rapid redox reaction is the synergistic result of superior catalytic response, large electrochemical-active surface area, high conductivity, and improved electron transfer pathways offered by the unique configuration of high porosity and metallic nano-micro-NP decoration.