Oxime-Based Dielectric Polymer with Robust Tailored Cross-Linking for Self-Healing Triboelectric Nanogenerators

Abstract

Recent advances in energy harvesting technologies have highlighted the development of self-healable triboelectric nanogenerators, which are capable of converting environmentally mechanical energy into electrical energy with high efficiency and sustainability. Previous research has faced limitations in enhancing the output performance of self-healable triboelectric devices, especially when utilizing soft polymers as negative triboelectric materials. In this study, we introduce a facile approach by utilizing robust oxime-based polymers, specifically designed for self-healing applications in triboelectric nanogenerators. In addition, we optimize the output performance of a triboelectric device composed of the oxime-based polymer and poly(dimethylsiloxane) as the positive and negative triboelectric materials, respectively. The oxime-polymers, synthesized through radical polymerization of a methacrylate-based prepolymer (p(MMA-tBS-HEMA-VMA)) and a cross-linkable agent (oxi-DMA), exhibit dynamic oxime-carbamate bonding, enabling the material to autonomously repair itself after damage. It is demonstrated that the inclusion of oxi-DMA not only confers self-healing properties but also significantly enhances the thermal, mechanical, and triboelectric performances of the devices. The optimized oxime-polymer with 40 wt % of oxi-DMA content and a film thickness of 300 +/- 1.8 mu m showcases superior triboelectric output, attributed to enhanced dielectric properties resulting from the material's adjustable free volumes. This work not only elucidates the relationship between polymer composition, cross-linking density, and triboelectric performance but also marks the first investigation into the triboelectric applications of self-healing oxime-based polymers, paving the way for future advancements in durable and efficient energy harvesting technologies.