Dual-Electrode Glass Ribbons Intended for Use in Microplasma-Based Sensors.

Area of Science:

• Materials Science
• Plasma Physics
• Analytical Chemistry

Background:

• Microplasma generation combined with optical multi-material fiber technologies offers potential for real-time diagnostics.
• Creating long-lasting microplasma devices for remote analysis is challenging due to fabrication defects and electrode issues.
• Post-functionalization of electrode surfaces is typically needed to extend plasma emission duration.

Purpose of the Study:

• To develop a novel microplasma device for real-time diagnostics using advanced fiber fabrication techniques.
• To overcome challenges in creating long, defect-free multimaterial fibers with continuous electrodes for microplasma generation.
• To enhance microplasma emission duration without post-fabrication surface treatments.

Main Methods:

• Utilized the stack-and-draw technique to fabricate rectangular glass fibers (ribbons) with an aluminum alloy core for electrodes.
• Controlled the cooling rate during fiber drawing between 200-300 °C/s to minimize defects and ensure low electrical resistivity.
• Investigated the in situ formation of an oxide layer on electrodes during plasma generation.

Main Results:

• Successfully fabricated defect-minimized glass ribbons with aluminum alloy electrodes using controlled cooling rates.
• Observed the spontaneous formation of an in situ oxide layer on electrode tips during plasma generation.
• Demonstrated a significant increase in plasma emission duration due to the in situ oxide layer, eliminating the need for post-functionalization.
• Integrated the fabricated ribbons with an optical emission spectrometer to create a miniature gas detector for hydrocarbons.

Conclusions:

• The developed glass-ribbon microplasma device offers a promising approach for real-time diagnostics.
• In situ oxide layer formation on aluminum alloy electrodes effectively extends plasma emission duration, simplifying fabrication.
• The miniature gas detector shows potential for sensitive hydrocarbon detection.