The fabrication of advanced electromagnetic wave absorbents with wide bandwidth, robust absorption and small filling ratio remains a great challenge. In this work, the ternary composite aerogel of nitrogen-doped reduced graphene oxide/nickel ferrite@silicon dioxide modified by amino groups (NRGO/NiFe₂O₄@m-SiO₂) was synthesized via the three-step route of solvothermal synthesis, Stöber method and hydrothermal self-assembly. Microscopic morphology characterization results indicated that the acquired binary and ternary magnetic composite aerogels exhibited a special three-dimensional porous network architecture. Moreover, the electromagnetic absorbing capacity of NRGO/NiFe₂O₄ composite aerogel could be obviously enhanced by coating SiO₂ and modifying amino groups on the surfaces of SiO₂. Remarkably, the as-fabricated NRGO/NiFe₂O₄@m-SiO₂ composite aerogel possessed the broadest effective absorption bandwidth of 7.04 GHz (10.96–18.0 GHz) and robust absorbing intensity of −30.8 dB at 2.1 mm under a small filling ratio of 12.5 wt%. It was worth mentioning that the optimal minimum reflection loss could reach −56.0 dB when the matching thickness was increased to 3.4 mm. Besides, a minimum radar cross section value of −51.1 dB m² could be achieved in the far-filed condition. The special porous network structure and magnetodielectric synergy in the ternary composite aerogel optimized the electromagnetic impedance, and notably enhanced the electromagnetic absorbing capacity. It was believed that this study would provide a novel approach for the construction of highly efficient carbon-based electromagnetic wave absorbers.

制造具有宽带宽、强吸收和小填充率的先进电磁波吸收剂仍然是一个巨大的挑战。本工作采用溶剂热合成三步法合成了氨基修饰的氮掺杂还原氧化石墨烯/铁酸镍@二氧化硅三元复合气凝胶（NRGO/NiFe ₂ O ₄ @m-SiO ₂ ）， Stöber 方法和水热自组装。微观形貌表征结果表明，所获得的二元和三元磁性复合气凝胶具有特殊的三维多孔网络结构。_{此外，NRGO/NiFe 2} O ₄的电磁吸收能力_{通过包覆SiO 2并修饰SiO 2}表面的氨基可以明显增强复合气凝胶的性能。值得注意的是，在小填充率下，制造的 NRGO/NiFe 2 O ₄ @ _m -SiO ₂复合气凝胶具有 7.04 GHz（10.96–18.0 GHz）的最宽有效吸收带宽和 2.1 mm 处 −30.8 dB 的稳健吸收强度12.5 重量％。值得一提的是，当匹配厚度增加到3.4 mm时，最佳最小反射损耗可达-56.0 dB。此外，最小雷达截面值为 −51.1 dB m ²可以在远场条件下实现。三元复合气凝胶中特殊的多孔网络结构和磁介电协同作用优化了电磁阻抗，显着增强了电磁吸收能力。相信这项研究将为构建高效碳基电磁波吸收器提供一种新方法。