Logarithmic Helical Design for Reversed Magnetic Field in Magnetoelastic Soft Matters with Giant Current Outputs.

Area of Science:

• Soft bioelectronics
• Wearable energy harvesting
• Magnetoelastic materials

Background:

• Magnetoelastic soft materials are crucial in soft bioelectronics.
• Existing materials exhibit limited electrical output due to minimal magnetic flux changes during mechanical deformation.

Purpose of the Study:

• To enhance magnetic flux density variation under mechanical force for improved electrical outputs.
• To develop high-performance wearable biomechanical energy harvesting devices.

Main Methods:

• Employed a two-step process involving helical structural design and mechanical strain induction.
• Utilized a logarithmic helical structure to achieve a complete 180° magnetic field reversal.
• Optimized material structure to maximize magnetic flux variation and current density.

Main Results:

• Achieved a 200% increase in magnetic flux variation with a peak current of 6.34 mA.
• Reached a current density of 7.17 mA cm^-2 after structural optimization.
• Developed a knee pad device demonstrating energy harvesting up to 2.83 mA from body movement.

Conclusions:

• The rationally designed logarithmic helix model significantly enhances magnetoelastic material performance.
• The developed wearable device offers a viable solution for powering small electronics using human motion.
• Represents a significant advancement in high-performance wearable biomechanical energy harvesting technology.