Kim So Young, Kim Ji Hong, Kim Kyeong Nam, Oh Hayoung, Myung Sung, Kim Do Hwan
Department of Chemical Engineering, Hanyang University, Seoul, 04763, Republic of Korea.
Clean-Energy Research Institute, Hanyang University, Seoul, 04763, Republic of Korea.
Sci Rep. 2024 Feb 26;14(1):4599. doi: 10.1038/s41598-024-55082-w.
Iontronic devices, recognized for user-friendly soft electronics, establish an electrical double layer (EDL) at the interface between ion gels and electrodes, significantly influencing device performance. Despite extensive research on ion gels and diverse electrode materials, achieving a stable interfacial formation remains a persistent challenge. In this work, we report a solution to address this challenge by employing CO irradiation as a bottom-up methodology to directly fabricate highly conductive, conformable laser-induced graphene (LIG) electrodes on a polyimide (PI)-based ion gel. The PI ion gel exhibits exceptional EDL formation at the electrode interface, primarily attributable to efficient ion migration. Particularly, ionic laser-induced graphene (i-LIG) electrodes, derived from the PI ion gel as a precursor, yield high-quality graphene with enhanced crystallinity and an expanded porous structure in the upward direction. This outcome is achieved through a pronounced thermal transfer effect and intercalation phenomenon between graphene layers, facilitated by the presence of ionic liquids (ILs) within the PI ion gel. Ultimately, in comparison to alternative soft electrode-based vertical capacitors, the utilization of i-LIGs and PI ion gels in the vertical capacitor demonstrates reduced interfacial resistance and increased EDL capacitance, emphasizing the extensive potential of iontronic devices. These results not only highlight these features but also introduce a new perspective for advancing next-generation iontronic devices.
离子电子器件以其用户友好型软电子特性而闻名，它在离子凝胶与电极之间的界面处形成双电层（EDL），对器件性能有重大影响。尽管对离子凝胶和各种电极材料进行了广泛研究，但实现稳定的界面形成仍然是一个长期挑战。在这项工作中，我们报告了一种解决这一挑战的方法，即采用CO辐照作为一种自下而上的方法，在基于聚酰亚胺（PI）的离子凝胶上直接制备高导电性、贴合性的激光诱导石墨烯（LIG）电极。PI离子凝胶在电极界面表现出优异的EDL形成，这主要归因于有效的离子迁移。特别是，由PI离子凝胶作为前驱体制备的离子激光诱导石墨烯（i-LIG）电极，可产生高质量的石墨烯，其结晶度提高，向上方向的多孔结构扩大。这一结果是通过PI离子凝胶中离子液体（ILs）的存在促进石墨烯层之间显著的热传递效应和插层现象而实现的。最终，与基于替代软电极的垂直电容器相比，在垂直电容器中使用i-LIG和PI离子凝胶显示出界面电阻降低和EDL电容增加，突出了离子电子器件的广泛潜力。这些结果不仅突出了这些特性，还为推进下一代离子电子器件引入了新的视角。
