Peroxide Sensing Using Nitrogen-Doped Screen-Printed Carbon Electrodes

• Main Authors: Ogbu, Chidiebere, Bishop, Gregory, Dr.
• Published: Digital Commons @ East Tennessee State University 2019
• Subjects: Nitrogen; Doped; Screen; Printed/Electrodes; Electrochemistry
• Online Access: https://dc.etsu.edu/asrf/2019/schedule/93

Nitrogen-doped carbon materials such as carbon nanotubes and graphene have garnered much interest due to their abilities to behave as electrocatalysts for reactions important in energy production (e.g. oxygen reduction) and biosensing (e.g. hydrogen peroxide reduction). Electrocatalytic properties of these materials have been attributed to enhanced electron transfer ability exhibited by surface nitrogen atoms compared to typical carbon structures. Screen-printing has been widely employed in the production of low-cost carbon-based electrodes for sensors and biosensors. Here, we develop nitrogen-doped screen-printed carbon (N-SPCE) electrodes for detection of hydrogen peroxide - an important analyte in biosensing. Conductive ink was formulated in the lab from nitrogen-doped graphite that was produced using a simple urea-based soft nitriding technique. N-SPCEs exhibited electrocatalytic activity towards hydrogen peroxide reduction, while SPCEs prepared from unmodified carbon showed no ability to electrocatalytically reduce H2O2. Amperometric detection of H2O2 using N-SPCEs at an applied potential of -0.4 V (vs. Ag/AgCl) displayed a wide linear range of 20 µM to 5.3 mM, and a low limit of detection (2.4 µM). These performance characteristics compare favorably to other electrodes for H2O2 sensing and indicate that the low-cost, easy-to-prepare N-SPCEs described here are promising platforms for the development of biosensors.