Sensitive Flow-Injection Electrochemical Determination of Hydrogen Peroxide at a Palladium Nanoparticle-Modified Pencil Graphite Electrode


KARAKAYA S. , DİLGİN Y.

ANALYTICAL LETTERS, vol.52, no.6, pp.998-1017, 2019 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 52 Issue: 6
  • Publication Date: 2019
  • Doi Number: 10.1080/00032719.2018.1509986
  • Title of Journal : ANALYTICAL LETTERS
  • Page Numbers: pp.998-1017
  • Keywords: Amperometry, flow injection analysis, hydrogen peroxide, palladium nanoparticles, pencil graphite electrode, WALLED CARBON NANOTUBES, POT GREEN SYNTHESIS, NICKEL FOAM, SENSOR, FABRICATION, ENZYME, H2O2, BIOSENSOR, NANOSPHERES, COMPOSITES

Abstract

A novel flow-injection amperometric method was proposed for the sensitive and enzymeless determination of hydrogen peroxide based on its electrocatalytic reduction at a palladium nanoparticle-modified pretreated pencil graphite electrode in a laboratory-constructed electrochemical flow cell. Cyclic voltammograms of the unmodified and modified electrodes were recorded in pH 7.0 phosphate buffer containing 0.10 M KCl at a scan rate of 50mV s(-1) for the investigation of electrocatalytic reduction of hydrogen peroxide at the palladium nanoparticle-modified pretreated pencil graphite electrode. Cyclic voltammograms of the pretreated pencil graphite electrode revealed an irreversible oxidation peak and a weak reduction peak of hydrogen peroxide at +1100mV and -450mV vs. an Ag/AgCl/KCl saturated reference electrode. However, the reduction of hydrogen peroxide was observed at -100mV with an increase in current in the cyclic voltammograms of the palladium nanoparticle-modified pretreated pencil graphite electrode compared to the unmodified electrode. These results indicate that the palladium nanoparticle-modified pretreated pencil graphite electrode exhibits efficient electrocatalytic activity for the reduction of hydrogen peroxide. A linear concentration range was obtained between .01 and 10.0mM hydrogen peroxide with a detection limit of 3.0 mu M from flow injection amperometric current-time curves recorded in pH 7.0 phosphate buffer at -100mV and a 2.0mL min(-1) flow rate. The novelty of this work relies on its use of a laboratory-constructed flow cell constructed for the pencil graphite electrode using these inexpensive, disposable, and electrochemically reactive modified electrodes for the amperometric determination of hydrogen peroxide in a flow injection analysis system.