Sensitive electrochemical sensor for gaseous hydrogen peroxide
The development of sensitive, selective, and reliable gaseous hydrogen peroxide (H2O2) sensors operating at room temperature still represents a remaining challenge. In this work, we have demonstrated a synergistic effect of the physicochemical properties of exfoliated Ti3C2Tx MXene and the stabilizing character of chitosan, together with the redox activity of ferrocyanide-modified screen-printed carbon electrode, in the development of a sensitive and selective sensor for point-of-interest detection of gaseous H2O2.
Researchers have combined the advantageous properties of a two-dimensional Ti3C2Tx MXene material that exhibits a large specific surface area and high surface activity, with beneficial conducting and stabilizing properties of chitosan. The MXene-chitosan membrane was deposited on the ferrocyanide-modified screen-printed working carbon electrode, followed by the application of polyacrylic acid as the electrolyte and accumulation medium for gaseous H2O2. The sensing membrane was thoroughly characterized by various techniques, such as XRD, Raman spectroscopy, SEM/STEM, EDXS, XPS, AFM, 3D ToF-SIMS, square-wave and cyclic voltammetry. The sensor showed excellent interference-free operation in the cathodic potential range, along with good sensor-to-sensor reproducibility, favorable stability, and a very low detection limit of only 4 μg m−3 (ppbv). The practical applicability of the gas sensor was successfully demonstrated by measuring H2O2 during the treatment of human hair with a bleaching agent.
The presented electrochemical sensing platform provides excellent support for the further development of simple, disposable, portable, and low-cost gas sensors operating at room temperature for various point-of-need applications in the fields of environmental monitoring, food safety, cultural heritage preservation, medical diagnostics, and homeland security measures.
The authors of this research are Samo Hočevar, Jelena Isailović, and Nikola Tasić from the Department of Analytical Chemistry (D04), Ana Oberlintner and Uroš Novak from the Department of Catalysis and Chemical Reaction Engineering (D13), Matjaž Finšgar from the Faculty of Chemistry and Chemical Engineering (UM), Filipa M. Oliveira, Jan Paštika, Zdeněk Sofer, and Rui Gusmão from the Department of Inorganic Chemistry, University of Chemistry and Technology Prague. The work is published in ACS Applied Materials & Interfaces (IF = 10.383).
Cover graphics: Scheme of the electrochemical sensor for cyclic voltammetric detection of gaseous hydrogen peroxide.
Contact pesron: samo.hocevar(at)ki.si