CuCo-Cu@CoCH stamen-like nanoarray prepared by co-reduction for electrochemical detection of hydrogen peroxide

Abstract Accurate and convenient detection of H2O2 is of great significance for the diagnosis and treatment to some diseases. Herein, a unique stamen-like CuCo-Cu@Co(CO3)0.5(OH) (defined as CuCo-Cu@CoCH) nanoarray was fabricated by cation exchange and co-reduction for electrochemical detection of H2O2. The nanostructure with large electrochemical surface area can adsorb H2O2 efficiently, while the Cu@CoCH nanowire offers a high-way for electron transfer, and the CuCo nanoparticle possesses high activity for H2O2 reduction. Hence, the CuCo-Cu@CoCH nanoarray performs excellently as a electrochemical H2O2 sensor with a high sensitivity of 3570 μA mM−1 cm−2 (1 μM to 100 μM) and 3290 μA mM−1 cm−2 (100 μM to 2000 μM), a fast response time (＜1.5 s), a low detection limit (0.97 μM, S/N = 3) and superior selectivity, stability. Furthermore, the nanoarray shows promising electrochemical activity for real-time detection of H2O2 released from HepG2 human liver cancer cells. This work offers a novel material as electrochemical sensor to H2O2 with enhanced performance, and shows a new solution to prepare nanostructure of alloy.