Hydroxyl adsorption derived reactive oxygen species from carbon paper-supported Cu2O for enhanced electrochemical glucose sensing

Abstract

Engineered sensitive copper nanostructured superelectrode systems have become an important part of electrochemical sensing of glucose because of their high sensitivity, specificity, abundant natural reserves, and environmental friendliness. However, the factors affecting the electrochemical catalytic activity of glucose remain a challenging issue, which largely limits the overall electrochemical sensing performance of glucose. This paper reports the design of a carbon fiber loaded cuprous oxide nanoparticle (Cu2O NPs) electrochemical sensor with electrochemical catalytic properties for glucose oxidation. The copper grown on carbon nanofibers was subjected to cyclic redox treatment to obtain Cu2ONPs with good glucose detection ability. The detection range of the prepared Cu2ONPs was 0.05 mM − 3 mM with a sensitivity of 3 mA mM−1 cm−2. The differences in the properties of copper and cuprous oxide are analyzed in depth and the reasons for the variability are explored. By observing the electrocatalytic behavior and oxygen evolution reaction behavior of the glucose oxidation process, we hypothesized that the difference in the oxygen source provided by hydroxyl adsorption would lead to the difference in the properties of cuprous oxide and copper. Our proposed differences in the oxygen source generated by hydroxyl adsorption affecting the performance of glucose detection will provide new ideas for the design of glucose electrochemical microelectrodes.