A highly sensitive nonenzymatic glucose sensor based on Cu/Cu2O composite nanoparticles decorated single carbon fiber

In this study, we reported a highly sensitive nonenzymatic glucose sensor based on Cu/Cu2O composite nanoparticles (Cu/Cu2O NPs) decorated on a single carbon fiber (SCF) by direct in-situ electrochemical cyclic voltammetry deposition. The scanning electron microscopy (SEM) study of the Cu/Cu2O NPs/SCF electrodes displayed a porous structure of Cu/Cu2O nanoparticles with an average size of around 30 nm, which greatly increased the surface area of single carbon fiber and provided a large number of catalysis sites towards glucose oxidation. The electrochemical behavior of Cu/Cu2O nanoparticles was characterized by cyclic voltammetry and amperometry study, in which the as-prepared electrode displayed superior catalytic performance and exhibited an ultra-high sensitivity (28,071 uA mM−1 cm−2) and a wide linear range up to 7.8 mM. The in-situ electrodeposition of Cu/Cu2O nanoparticles and excellent conductivity of carbon fiber improved the electron transfer rate due to direct electron collection and resulted in a short response time (<1 s). Additionally, the electrode also showed good reproducibility, outstanding anti-interference ability and long-time stability, as well as a reliable testing result in bovine serum sample, indicating a potential application in clinical diagnosis and health monitoring.