In the practical application of electromagnetic wave (EMW) absorbers, two important factors that simultaneously meet the lightweight characteristics and efficient absorption performance still face considerable challenges. In this work, the ultra-lightweight CoNi alloy nanoparticles uniformly distributed modified carbon nanofiber composites (CoNi@CNFs) was prepared by an ion-etching strategy. The carbon fibers create a three-dimensional conductive network that enhances the absorber’s conduction loss capability. The polarization loss is enhanced by the defects in the carbon skeleton and the numerous heterogeneous interfaces formed between the carbon fibers and the surface of CoNi metal particles. The impedance matching property of CoNi@CNFs is optimized by the magnetic dielectric synergistic effect produced by the Ni²⁺ etching process. At a frequency of 17.58 GHz, the minimum reflection loss (RL_min) can reach − 52.34 dB, and the effective absorption bandwidth covers the complete Ku band at 7.0 GHz (11.0–18.0 GHz). In the range of − 60° to 60°, the radar cross-section values of the samples, calculated using CST simulation, are less than − 10 dBm². This is critical for realizing the stealth capability of EMWs in high-frequency environments. This study provides an effective strategy for developing highly absorbent, lightweight EMW absorbers with practical potential applications.

Graphical Abstract

中文翻译：

---

利用离子刻蚀策略构建超轻质CoNi合金改性电纺碳纤维复合材料以实现高效电磁波吸收

在电磁波（EMW）吸收体的实际应用中，同时满足轻量化特性和高效吸收性能的两个重要因素仍然面临着相当大的挑战。在这项工作中，通过离子刻蚀策略制备了超轻CoNi合金纳米粒子均匀分布的改性碳纳米纤维复合材料（CoNi@CNFs）。碳纤维形成三维导电网络，增强吸收器的传导损耗能力。碳骨架中的缺陷以及碳纤维和CoNi金属颗粒表面之间形成的大量异质界面增强了极化损耗。 CoNi@CNFs的阻抗匹配特性通过Ni ²⁺蚀刻过程产生的磁介电协同效应得到优化。在17.58 GHz频率下，最小反射损耗（RL _min）可达− 52.34 dB，有效吸收带宽覆盖7.0 GHz（11.0-18.0 GHz）的完整Ku频段。在− 60°至60°范围内，利用CST模拟计算的样本雷达截面值小于− 10 dBm ²。这对于在高频环境中实现电磁波的隐身能力至关重要。这项研究为开发具有实际潜在应用的高吸收性、轻质电磁波吸收器提供了有效的策略。

图形概要