High Performance KNN-Based Macro Fiber Composites for Human Motion Monitoring Applications.

Area of Science:

• Materials Science
• Nanotechnology
• Sensor Technology

Background:

• Piezoelectric macro fiber composites (MFCs) are vital for smart electronics and IoT sensors.
• Current MFCs often rely on toxic lead-based materials, limiting bio-friendly applications.
• Developing lead-free alternatives is crucial for sustainable intelligent electronics.

Purpose of the Study:

• To develop a lightweight, thin, high-performance, lead-free MFC for human motion monitoring.
• To utilize multilevel structure engineered (K,Na)NbO3-based ceramics as an eco-friendly piezoelectric matrix.
• To provide a fundamental methodology for lead-free MFC development.

Main Methods:

• Finite element analysis (FEA) was employed to simulate electric fields and piezo-potential.
• Multilevel structure engineered (K,Na)NbO3-based ceramics were used for the piezoelectric matrix.
• Electrical output signals were tested under various deformation modes.

Main Results:

• The developed lead-free MFC achieved high output voltage (≈25 V) and current (≈25 µA).
• An instantaneous output power density of 80.42 µW cm⁻² was recorded.
• The MFC demonstrated sensitive electrical response to subtle human body motions.

Conclusions:

• The novel lead-free MFC offers a viable, eco-friendly alternative for human motion monitoring.
• This research establishes a foundational approach for next-generation lead-free piezoelectric sensors.
• The developed material enables sensitive energy harvesting from low-frequency body movements.