Influence of the Ozonation Process on Expanded Graphite for Textile Gas Sensors

Area of Science:

• Materials Science
• Textile Engineering
• Sensor Technology

Background:

• Growing demand for flexible, conductive materials in textile gas sensors.
• Expanded graphite (EG) as a promising material for functional textiles.
• Need to optimize surface modification techniques for enhanced material properties.

Purpose of the Study:

• To investigate the effects of ozonation on expanded graphite (EG) properties within textile structures.
• To evaluate the impact of different ozonation durations (15 min and 30 min) on EG-coated fabrics.
• To determine the suitability of ozonated EG for textile gas sensor applications.

Main Methods:

• Coating four fabric types (cotton, polyamide, viscose, para-aramid) with EG-based paste via screen printing.
• Subjecting EG pastes to 15-min and 30-min ozonation processes.
• Analyzing surface resistance, scanning electron microscopy (SEM), and wetting angle of the modified fabrics.

Main Results:

• Short-term ozonation (15 min) significantly improved electrical conductivity and EG adhesion to textile substrates.
• Longer ozonation (30 min) resulted in decreased conductivity due to excessive functionalization and conductive layer fragmentation.
• The lowest surface resistance was achieved with 15-min ozonation, indicating optimal modification.

Conclusions:

• Controlled ozonation is effective in enhancing EG for textile sensor applications, particularly for smart clothing.
• Optimizing ozonation time is critical to maintain the conductive layer's integrity and durability.
• Ozonation presents a viable method for tailoring EG properties for advanced functional textiles.