High-density, highly sensitive sensor array of spiky carbon nanospheres for strain field mapping

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Accurate strain mapping is vital for stress analysis and fatigue life prediction in engineering.
• Conventional strain sensors struggle to balance high sensitivity with sensing density.
• Developing advanced strain mapping techniques is essential for reliable engineering assessments.

Purpose of the Study:

• To develop a novel strain sensor array with enhanced sensitivity and sensing density.
• To investigate the application of Fowler-Nordheim tunneling in spiky carbon nanosphere arrays for strain sensing.
• To enable accurate strain distribution mapping on diverse and conformal surfaces.

Main Methods:

• Fabrication of a strain sensor array using monodispersed spiky carbon nanospheres on polydimethylsiloxane.
• Utilizing the Fowler-Nordheim tunneling effect for strain detection.
• Characterization of sensor performance, including sensitivity, sensing density, linearity, and inter-unit consistency.

Main Results:

• Achieved a high sensitivity of up to 70,000 and a sensing density of 100 pixels cm^-2.
• Demonstrated logarithmic linearity over 99% within a broad strain range (0% to 60%).
• Exhibited high inter-unit consistency with a standard deviation ≤3.82% due to ordered nanosphere assembly.

Conclusions:

• The developed spiky carbon nanosphere strain sensor array offers a significant advancement in strain mapping capabilities.
• Its high performance and conformal coverage make it suitable for various applications including flexible electronics, soft robotics, biomechanics, and structural health monitoring.
• This technology provides a convenient and accurate approach for acquiring strain field data.