Cao Ying, Yang Kaiyu, Ke Haibo, Fu Lishi, Yan Xitong, Xian Jinghuan, Lin Mingyuan, Cai Weiwei, Zhang Xue-Ao, Mu Rui, Zhang Yufeng
College of Physical Science and Technology, Xiamen University, Xiamen 361005, China.
Jiujiang Research Institute of Xiamen University, Jiujiang, 360404, China.
Nanoscale. 2025 Apr 10;17(15):9534-9540. doi: 10.1039/d5nr00322a.
Actively controlling the infrared (IR) emissivity of materials is critical for numerous applications, such as radiative cooling and thermal camouflage. Multilayer graphene (MLG) has shown significant potential as a functional material with tunable IR emissivity. However, the poor long-term stability of currently reported MLG-based IR modulators greatly limits their practical applications. Herein, ionic liquid gel electrolytes (ILGPEs) are prepared and used as doping sources to assemble MLG-based IR modulators with a sandwich-like structure. The modulator lifetime is dramatically improved, while the modulation depth and dynamic response are retained at levels comparable to those using pure ionic liquids. Microscopic structural analyses, including Raman spectroscopy and X-ray diffraction, are correlated with the ionic conductivity of the ILGPE and the IR radiation of the MLG. The results indicate that the improvement in device performance is likely due to an improved interface between the ILGPE and MLG, as well as limited ion diffusion within the ILGPE, which preserves the structural integrity of the MLG. These findings shed light on the optimization of IR modulators based on ion intercalation.
积极控制材料的红外（IR）发射率对于众多应用至关重要，如辐射冷却和热伪装。多层石墨烯（MLG）作为一种具有可调红外发射率的功能材料已显示出巨大潜力。然而，目前报道的基于MLG的红外调制器较差的长期稳定性极大地限制了它们的实际应用。在此，制备了离子液体凝胶电解质（ILGPEs）并用作掺杂源，以组装具有三明治状结构的基于MLG的红外调制器。调制器寿命得到显著提高，同时调制深度和动态响应保持在与使用纯离子液体相当的水平。包括拉曼光谱和X射线衍射在内的微观结构分析与ILGPE的离子电导率和MLG的红外辐射相关。结果表明，器件性能的提高可能是由于ILGPE与MLG之间界面的改善，以及ILGPE内有限的离子扩散，这保持了MLG的结构完整性。这些发现为基于离子插层的红外调制器的优化提供了启示。
