A novel enzyme-free glucose and H<inf>2</inf>O<inf>2</inf>sensor based on 3D graphene aerogels decorated with Ni<inf>3</inf>N nanoparticles

Abstract

© 2018 Elsevier B.V. In this work, a novel enzyme-free glucose and hydrogen peroxide (H2O2) sensor based on Ni3N nanoparticles on conductive 3D graphene aerogels (Ni3N/GA) has been successfully synthesized by using hydrothermal reaction, freeze-dried and then calcined under NH3atmosphere. The obtained Ni3N/GA composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), nitrogen adsorption–desorption isotherms and electrochemical methods. The results show the obtained 3D Ni3N/GA composites exhibit excellent electrochemical performance toward glucose oxidation and H2O2reduction with larger catalytic rate constant Kcatvalue of 3.75 × 103M-1s-1and 1.24 × 103M-1s-1, respectively. As a glucose sensor, the obtained electrode provides a wide detection range of 0.1–7645.3 µM, fast response time within 3 s, high sensitivity of 905.6 µA mM-1cm-2and low detection limit of 0.04 µM. For detection of H2O2, this prepared sensor offers a wide detection range (5 µM–75.13 mM), fast response time (within 5 s), sensitivity (101.9 µA mM-1cm-2) and low detection limit (1.80 µM). This enzyme-free glucose and H2O2sensor display satisfactory selectivity, reproducibility and long-term storage stability. Additionally, the sensor can also be used for glucose and H2O2detection in human blood serum. The results demonstrate that 3D GA nanostructures provide an enviable conductive network for efficient charge transfer and avoid Ni3N nanoparticles aggregation, which is advantageous for electrocatalytic applications.