Disposable manganese oxide screen printed electrodes for electroanalytical sensing

Area of Science:

• Electrochemistry
• Materials Science
• Analytical Chemistry

Background:

• Screen-printed graphite electrodes (SPGEs) are versatile platforms for electrochemical sensing.
• Manganese dioxide (MnO2) is a promising material for electro-catalysis due to its redox properties.

Purpose of the Study:

• To fabricate and evaluate MnO2-modified SPGEs for electro-analytical sensing.
• To investigate the potential of these electrodes for oxygen reduction reactions relevant to energy storage.

Main Methods:

• Fabrication of MnO2-modified SPGEs.
• Electrochemical characterization using cyclic voltammetry and amperometry.
• Evaluation of sensing performance for nitrite ions and ascorbic acid.
• Assessment of oxygen reduction reaction (ORR) activity.

Main Results:

• The fabricated MnO2/SPGEs demonstrated high electro-catalytic activity for nitrite and ascorbic acid detection.
• Achieved detection limits were comparable to or lower than existing electrochemical sensors.
• The electrodes facilitated a four-electron oxygen reduction to water, but required a significant overpotential.
• The disposable nature and cost-effectiveness were highlighted.

Conclusions:

• MnO2/SPGEs are effective platforms for the electro-analytical sensing of nitrite and ascorbic acid.
• While promising for sensing, the high overpotential for ORR needs further optimization for energy storage applications.
• The developed sensors offer a cost-effective and disposable solution for specific analytical tasks.