Non-enzymatic electrochemical sensor based on Cu2O/AuCu/Cu composite for hydrogen peroxide detection

A novel electrochemical non-enzymatic sensor based on a Cu2O/AuCu/Cu composite for hydrogen peroxide (H2O2) detection was designed. The lamellar structure of the Cu2O/AuCu/Cu composite without surfactants, which was easily prepared in 10 s using one-step electrochemical deposition, can expose more active sites for the catalysis of H2O2. This sensor reached the maximum steady-state current within 1 s after the addition of different concentrations of H2O2. Due to the excellent electronic conductivity of Au and Cu, the electron transfer was easily facilitated in the electrocatalytic process towards the reduction of H2O2. Results revealed that the electrochemical sensor exhibited a detection limit of 0.14 μM H2O2 (S/N = 3), detection range of 0.3–9000 μM, and high sensitivity of 159.12 μA mM−1 in 0.3–10 μM and 127.98 μA mM−1 in 10–9000 μM in 0.1 M phosphate buffer solution at −0.25 V (vs Ag/AgCl).