Du Lifei, Li Yuekun, Zhou Qian, Zhang Liangqing, Shi Tiantian, Wang Xinlei, Zhang Jinshang, Zhao Jing, Wang Jiong, Fan Xiaomeng
College of Materials Science and Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
College of Materials Science and Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
J Colloid Interface Sci. 2025 Feb;679(Pt A):987-994. doi: 10.1016/j.jcis.2024.10.057. Epub 2024 Oct 12.
Graphene aerogels, as a novel type of carbon-based composite material, have shown great potential in the field of wave absorption due to its characteristics of high conductivity, adjustable structure and good corrosion resistance. It is of great significance to precisely control the dielectric properties of graphene aerogel composites by effectively adjusting their microstructures through the preparing process design, ultimately leading to improve their wave-absorbing performances. In this study, two kinds of graphene/cellulose aerogel composites with three-dimensional porous structures, were successfully prepared using graphene and short staple cellulose as raw materials via the freeze-drying method based on the dissolution-regeneration strategy. A comparative analysis was conducted to examine the differences of microstructures, dielectric properties and corresponding electromagnetic wave absorption performances, which reveals that the graphene/cellulose aerogel composites with graphene nanosheets incorporated into the cellulose matrix realize superior absorbing performances. The graphene/cellulose aerogel composite with a 32 wt% graphene addition realizes effective electromagnetic wave absorbing (reflection loss less than -10 dB) in the whole X-band (8-12.4 GHz) in a relatively large thickness range (3.9-4.7 mm). The densities of the proposed aerogel are no more than 0.02 g/cm, demonstrating great potential for excellent lightweight microwave absorbing materials. The multiscale electromagnetic wave absorption mechanism is summarized, which would provide an important reference for designing ultra-lightweight absorbing materials with perfect absorption in wideband.
石墨烯气凝胶作为一种新型的碳基复合材料，因其具有高导电性、可调节结构和良好的耐腐蚀性等特点，在吸波领域展现出了巨大的潜力。通过制备工艺设计有效调整其微观结构，精确控制石墨烯气凝胶复合材料的介电性能，最终提高其吸波性能，具有重要意义。在本研究中，以石墨烯和短纤维纤维素为原料，基于溶解-再生策略，通过冷冻干燥法成功制备了两种具有三维多孔结构的石墨烯/纤维素气凝胶复合材料。进行了对比分析，以研究微观结构、介电性能及相应的电磁波吸收性能的差异，结果表明，石墨烯纳米片嵌入纤维素基体的石墨烯/纤维素气凝胶复合材料具有优异的吸收性能。添加32 wt%石墨烯的石墨烯/纤维素气凝胶复合材料在较宽的厚度范围（3.9-4.7 mm）内，在整个X波段（8-12.4 GHz）实现了有效的电磁波吸收（反射损耗小于-10 dB）。所制备气凝胶的密度不超过0.02 g/cm³，显示出作为优异轻质微波吸收材料的巨大潜力。总结了多尺度电磁波吸收机制，这将为设计在宽带内具有完美吸收性能的超轻质吸收材料提供重要参考。
