Large-Area 2D Metasurface-Based Triboelectric E-Skin Arrays: Contact & Proximity Tactile Mapping with Broadband...

Area of Science:

• Materials Science
• Nanotechnology
• Wearable Technology

Background:

• Capacitive triboelectric nanogenerators (TENGs) are key for self-powered flexible electronic skins, acting as sensors and energy harvesters.
• Enhancing TENG functionality in wearable tech requires optimizing electromechanical coupling, often through 2D dielectric metasurfaces.

Purpose of the Study:

• To develop a 2D metasurface-TENG electronic skin integrating tactile and acoustic sensing capabilities.
• To engineer nanocone (NC) metasurfaces for improved triboelectric charge density and optical strain monitoring.
• To demonstrate a self-powered, ultrathin platform for multimodal sensing.

Main Methods:

• Fabrication of large-area NC metasurfaces on polydimethoxysilane (PDMS) films using laser-interference lithography (LIL) and soft molding.
• Integration of the NC-TENG into a 3x3 array for tactile pressure imaging and proximity detection.
• Characterization of the device as a self-powered acoustic sensor, analyzing sound pressure level and frequency response.

Main Results:

• The NC metasurface significantly boosted triboelectric charge density and open-circuit voltage by approximately 46% compared to pristine PDMS.
• The arrayed e-skin achieved real-time tactile pressure imaging with low crosstalk and non-contact proximity sensing.
• The device demonstrated effective self-powered acoustic sensing across a broad frequency range (50-6400 Hz).

Conclusions:

• The developed 2D metasurface-TENG e-skin successfully integrates multimodal sensing (tactile and acoustic) on a single platform.
• Metasurface engineering enhances electromechanical coupling and electrical output stability, advancing TENG performance.
• This work paves the way for next-generation human-machine interfaces and wearable sensing applications.