Flexible FLIG-Based Temperature Sensor Enabled by Femtosecond Laser Direct Writing for Thermal Monitoring in Health...

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Flexible temperature sensors are crucial for wearable electronics and human-machine interfaces.
• Existing fabrication methods often involve complex processes or lack scalability.
• Graphene's unique properties make it a promising material for advanced sensor applications.

Purpose of the Study:

• To develop a facile and mask-free method for fabricating porous graphene-based flexible temperature sensors.
• To optimize sensor performance by tuning laser processing parameters.
• To demonstrate the sensor's integration and applicability in real-world scenarios.

Main Methods:

• Fabrication of porous graphene patterns on polyimide substrates using femtosecond laser direct writing (FLDW).
• Systematic adjustment of laser scanning spacing to control microstructure density and thermal sensitivity.
• Characterization of sensor performance, including temperature coefficient, response/recovery times, and signal stability.
• Integration of the sensor into a 3D-printed robotic platform for practical testing.

Main Results:

• Optimized FLDW produced dense microstructures with enhanced thermal sensitivity.
• Achieved a temperature coefficient of 0.698% °C⁻¹ within the 40-120 °C range.
• Demonstrated rapid response (10.3 s) and recovery (20.9 s) times with excellent signal stability.
• Successfully implemented the sensor for both contact and non-contact temperature detection on a robotic platform.

Conclusions:

• The FLDW approach offers a viable and scalable method for fabricating high-performance flexible graphene temperature sensors.
• The developed sensors exhibit excellent thermal sensitivity, stability, and rapid response.
• These sensors hold significant potential for applications in wearable electronics, electronic skin, and intelligent interfaces.