Electrochemical Behavior of Gold Nanoparticles Modified Nitrogen Incorporated Tetrahedral Amorphous Carbon and Its Application in Glucose Sensing

Gold nanoparticles (NPs) with 10–50 nm in diameter were synthesized on nitrogen incorporated tetrahedral amorphous carbon (ta-C:N) thin film electrode by electrodeposition. The deposition and nucleation processes of Au on ta-C:N surface were investigated by cyclic voltammetry and chronoamperometry. The morphology of Au NPs was characterized by scanned electron microscopy. The electrochemical properties of Au NPs modified ta-C:N (ta-C:N/Au) electrode and its ability to sense glucose were investigated by voltammetric and amperometric measurements. The potentiostatic current-time transients showed a progressive nucleation process and diffusion growth of Au on the surface of ta-C:N film according to the Scharifker-Hills model. The Au NPs acted as microelectrodes improved the electron transfer and electrocatalytic oxidation of glucose on ta-C:N electrode. The ta-C:N/Au electrode exhibited fast current response, a linear detection range of glucose from 0.5 to 25 mM and a detection limit of 120 μM, which hinted its potential application as a glucose biosensor.