The sustainable cellulose nanofibril (CNF) was efficiently utilized to facilitate the preparation of a type of ultralight, high-porosity carbon nanotube (CNT) hybrid aerogel-based electromagnetic wave (EMW) absorbers. CNF not only serves as a green surfactant to avoid the agglomeration of CNT, but also acts as supporting matrix or binder to promote the construction of porous CNT-based aerogels. Furthermore, the CNF precursor contributes to the generation of CNF-derived nanocarbon (CNFC) for a high-efficiency dielectric modulator, leading to the tuneable electromagnetic parameters and good impedance matching. Combined with the loss capacity of CNFC, the EMW absorption performance of CNT-based aerogels is enhanced. Consequently, the hybrid aerogels show EMW absorption performance involving an effective absorption bandwidth of 3.3 GHz and an ultrahigh reflection loss of −76.46 dB at a filling ratio of 5 wt%, outperforming that of other CNT-based EMW absorbers ever reported. The synergistic effects of multiple EMW absorption mechanisms for the hybrid aerogels were analyzed at length, demonstrating the indispensable roles of the CNF or CNFC in constructing high-efficiency CNT-based EMW absorbers. Combined with the green, sustainable, facile, and scalable preparation approach, the carbon aerogel-based EMW absorbers are highly promising for applications in electromagnetic compatibility or protection and aerospace.

可持续的纤维素纳米纤维（CNF）被有效地利用来促进一种超轻、高孔隙率碳纳米管（CNT）混合气凝胶基电磁波（EMW）吸收剂的制备。CNF不仅作为绿色表面活性剂避免CNT团聚，而且作为支撑基质或粘合剂促进多孔CNT基气凝胶的构建。此外，CNF 前驱体有助于生成 CNF 衍生的纳米碳 (CNFC)，用于高效介电调制器，从而实现可调谐的电磁参数和良好的阻抗匹配。结合CNFC的损耗能力，CNT基气凝胶的EMW吸收性能得到增强。因此，混合气凝胶表现出电磁波吸收性能，有效吸收带宽为3。3 GHz，填充率为 5 wt% 时具有 -76.46 dB 的超高反射损耗，优于迄今为止报道的其他基于 CNT 的 EMW 吸收体。详细分析了混合气凝胶的多种电磁波吸收机制的协同效应，证明了 CNF 或 CNFC 在构建高效基于 CNT 的电磁波吸收体中不可或缺的作用。结合绿色、可持续、简便和可扩展的制备方法，碳气凝胶基电磁波吸收剂在电磁兼容或防护和航空航天领域的应用前景广阔。证明了 CNF 或 CNFC 在构建高效 CNT 基 EMW 吸收器中不可或缺的作用。结合绿色、可持续、简便和可扩展的制备方法，碳气凝胶基电磁波吸收剂在电磁兼容或防护和航空航天领域的应用前景广阔。证明了 CNF 或 CNFC 在构建高效 CNT 基 EMW 吸收器中不可或缺的作用。结合绿色、可持续、简便和可扩展的制备方法，碳气凝胶基电磁波吸收剂在电磁兼容或防护和航空航天领域的应用前景广阔。