Title:Interfacing Silver Nanoparticles with Hematene Nanosheets for the
Electrochemical Sensing of Hydrogen Peroxide
Volume: 19
Issue: 8
Author(s): Kavitha Rani Thirumoorthi and Kiran Kumar Tadi*
Affiliation:
- Division of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Chennai, 600 127, India
Keywords:
Hydrogen peroxide sensing, silver nanoparticles, hematene, 2-dimensional nanomaterials, chronoamperometry, ROS.
Abstract:
Background: Hydrogen peroxide (H2O2) is an important metabolite that plays a crucial role in
enzymatic reactions in living organisms. However, it acts as a reactive oxygen species (ROS) that causes
various chronic diseases. The main challenging aspects in detecting H2O2 in body cells are the ultra-lowlevel
concentrations and its reactivity. Hence, it is highly essential to develop a platform for H2O2 with
high sensitivity and selectivity.
Objective: In this work, we report an electrochemical biosensor for hydrogen peroxide (H2O2) by
interfacing 3-dimensional silver nanoparticles (Ag-NPs) with 2-dimensional hematene (HMT)
nanosheets.
Methods: The two-dimensional nanomaterial, HMT, was exfoliated from natural iron ore hematite (α-
Fe2O3) and characterized by Raman spectroscopy. The morphology of the Ag nanoparticles and HMT
was imaged by scanning electron microscope. Electrochemical characterization of Ag/HMT modified
glassy carbon electrode (GCE) was performed by cyclic voltammetry (CV) and electrochemical
impedance spectroscopy (EIS).
Results: The fabricated sensor showed a wide linearity range of H2O2 concentrations from 0.99 μM to
1110 μM and a low detection limit of 0.16 μM using CV. Further, the sensor was successfully applied for
the electrochemical sensing of hydrogen peroxide using chronoamperometry (CA) from 20 μM to 1110
μM (LOD 5.5 μM).
Conclusion: The proposed electrochemical sensor for H2O2 is fast responding with a high sensitivity, and
shows selectivity in the presence of biologically important molecules. These consequences suggested that
the formation of heterostructures between 2D and 3D nanomaterials unveils the possibility of stable and
selective electrochemical sensors for bioanalytics.