Liquid-Metal-Assisted Piezo-Triboelectric Nanogenerator for High-Efficiency Energy Harvesting

Abstract:

Achieving high-performance polymer-based piezoelectric-triboelectric nanogenerators (PTNGs) remains challenging due to the limited electroactive phase content and inefficient dipole alignment in polymer matrices. Here, we propose a liquid-metal doping strategy, supported by molecular dynamics (MD) simulations, to construct β-PVDF-LM composites with enhanced pie-zoelectric and triboelectric properties. Simulations indicate that liquid-metal atoms preferentially interact with fluorine in PVDF chains, stabilizing the all-trans conformation and promoting dipole ordering under an external electric field. In addition, the liquid metal and its native oxide layers act as electron-trapping centers during triboelectric contact, leading to higher interfacial charge storage and retention. As a result, the β-PVDF-LM composites exhibit a high β-phase fraction of 91% and deliver outstanding electrical outputs. The optimized β-PVDF-LM/PA6 PTNG achieves a peak-to-peak voltage of 1831 V, a current density of 214.3 mA/m², a charge density of 254.4 μC/m², and a maximum power density of 83.8 W/m². This work provides new in-sights into the design of liquid-metal-assisted PTNGs and highlights their potential for efficient energy harvesting.

• Periodical: Advances in Science and Technology (Volume 175)
• Pages: 33-38
• DOI: https://doi.org/10.4028/p-mrJnW7
• Online since: May 2026
• Authors: Jia Qi Lu*, Liang Quan Xu, Ji Kui Luo
• Keywords: Energy Harvesting, Liquid Metal Dop-Ing, Piezoelectric-Triboelectric Nanogenerator, β-Phase PVDF

References

[1] Lee, G. H. et al. Multifunctional materials for implantable and wearable photonic healthcare devices. Nat. Rev. Mater. 5, 149–165 (2020).

[2] Xu, L. et al. Universal Analysis Method for Metamaterial-Based Wireless Power Transfer with Arbitrary Energy Source Waveforms: Application to Triboelectric Nanogenerators. ACS Appl. Mater. Interfaces 17, 9243–9252 (2025).

DOI: 10.1021/acsami.4c17818

[3] Lu, J. et al. Piezoelectric nanogenerator enabled fully self-powered instantaneous wireless sensor system. Nano Energy 129, 110022 (2024).

DOI: 10.1016/j.nanoen.2024.110022

[4] Hazarika, D. et al. Ion dipole interaction and directional alignment enabled high piezoelectric property polyvinylidene fluoride for flexible electronics. npj Flex. Electron. 9, (2025).

DOI: 10.1038/s41528-025-00393-9

[5] Sun, S. et al. A shape-adaptable and highly resilient aerogel assembled by poly(vinylidene fluoride) nanofibers for self-powered sensing. Nano Energy 116, 108820 (2023).

DOI: 10.1016/j.nanoen.2023.108820

[6] Ribeiro, C. et al. Electroactive poly(vinylidene fluoride)-based structures for advanced applications. Nat. Protoc. 13, 681–704 (2018).

DOI: 10.1038/nprot.2017.157

[7] Mohammadpourfazeli, S. et al. Future prospects and recent developments of poly-vinylidene fluoride (PVDF) piezoelectric polymer; fabrication methods, structure, and electro-mechanical properties. RSC Adv. 13, 370–387 (2023).

DOI: 10.1039/d2ra06774a

[8] Lu, J. & Hazarika, D. High-performance Self-polarized piezoelectric PVDF compo-sites films for tribo-electric nanogenerators. J. Phys. Conf. Ser. 2809, (2024).

DOI: 10.1088/1742-6596/2809/1/012011

[9] Lu, J. et al. GaIn-Induced Polarization Control in PVDF for High-Ef fi ciency Energy Harvesting and Instantaneous Wireless Sensing. Energy Environ. Mater. 1–14 (2025).

DOI: 10.1002/eem2.70201

[10] Zhang, K. et al. Nanosheet-Doped Polymer Composites with High Intrinsic Piezoelectric Properties for Energy Harvesting. Energy Environ. Mater. 1–12 (2024).

DOI: 10.1002/eem2.12789

[11] Lu, J. et al. Synthesis of High-Performance Polyvinylidene Fluoride Composites via Hydroxyl Anchoring Effect and Directional Freeze-Drying Method. Adv. Energy Sustain. Res. 2300237, (2024).

DOI: 10.1002/aesr.202300237