Highly Transparent, Flexible, and Ultrathin Piezocomposite with Moth-Eye-Inspired Nanopatterns for Self-Cleaning and Water Droplet Energy-Harvesting

Abstract

In this study, a piezoelectric nanogenerator (PENG) integrated with a moth-eye nanopatterned (MENP) perfluoropolyether (PFPE) film was fabricated using electrospinning, metal electroplating, spin-coating, and photolithography. The combination of these techniques enables the ultrathin MENP-PENG to possess high transparency, high sensitivity, and enhanced energy-harvesting performance, which are difficult to achieve simultaneously in conventional PENGs. Under an 11 mg water droplet impact, the MENP-PENG generated an output voltage of 1.0 V through a morphology-assisted hybrid response involving deformation-mediated piezoelectric transduction of the piezoelectric layer and liquid–solid contact electrification/electrostatic induction at the MENP/water interface, corresponding to a static-equivalent gravitational load of 100 μN. Owing to its self-cleaning and anti-reflective properties, the MENP-PENG shows potential as a transparent protective platform for electric vehicle camera modules. These results demonstrate that the materials design and fabrication strategy proposed here provide an effective route toward transparent, flexible, and high-performance PENGs for emerging electric vehicle camera applications.

Keywords

Electrospun P(VDF-TrFE) nanofibers / Nickel-electroplated microfibers / Moth-eye-inspired nanopattern / Piezoelectric nanogenerator / Self-cleaning / Water droplet energy-harvesting

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Funding

Korea Institute for Advancement of Technology(RS-2023-KI002684)

Ministry of Science and ICT, South Korea(RS-2026-25469971)

Rights & permissions

Donghua University, Shanghai, China