Nanostructured magnetic metal/reduced graphene oxide (rGO) composites, benefiting from well-performed losses including high dielectric/magnetic losses, have garnered considerable interest as advanced microwave absorbers (MAs) in recent years. Optional approaches of unique trimetallic/rGO nanostructures, however, are still limited to attain high electromagnetic (EM) absorption and broad bandwidth as well as improved impedance matching. Herein, porous flower-like FeCoNi/rGO nanosheets, synthesized via magnetic-field-assisted (MFA) reduction, presents facilitated microwave absorption performance. The zigzag-like attachments of neighbored nanosheets constitute the porous flower-like architecture; average thickness of the nanosheets is 5–20 nm. The reduction process, determined by appropriate GO dosage, plays a key role to tune geometry and distribution of the flower-like nanosheet structures. The optimal sample, owning a relatively high surface area (157.3 m² g⁻¹), achieves an impressive reflection loss (RL) intensity of − 75.95 dB and its maximum effective absorption bandwidth (RL ≤ −10 dB) is up to 4.69 GHz, along with improved impedance matching. This work provides a facile and alternative route for exploring other novel nanoalloy-based MAs.

纳米结构磁性金属/还原氧化石墨烯 (rGO) 复合材料受益于良好的损耗，包括高介电/磁损耗，近年来作为先进的微波吸收器 (MA) 引起了相当大的兴趣。然而，独特的三金属/rGO 纳米结构的可选方法仍然受限于实现高电磁 (EM) 吸收和宽带宽以及改进的阻抗匹配。在此，通过磁场辅助（MFA）还原合成的多孔花状 FeCoNi/rGO 纳米片具有良好的微波吸收性能。相邻纳米片的锯齿状连接构成了多孔的花状结构；纳米片的平均厚度为 5-20 nm。还原过程，由适当的 GO 剂量决定，在调整花状纳米片结构的几何形状和分布方面起着关键作用。最佳样品，拥有相对较高的表面积（157.3 m² g ^-1 )，实现了令人印象深刻的反射损耗 (RL) 强度 - 75.95 dB，其最大有效吸收带宽 (RL ≤ -10 dB) 高达 4.69 GHz，同时改进了阻抗匹配。这项工作为探索其他新型纳米合金基 MA 提供了一条简便的替代途径。