Constructing efficient electromagnetic wave (EMW) absorbers with broad bandwidth and high absorption is critical for mitigating electromagnetic pollution. Here, (Ni,Co)₃ZnC_0.7/melamine sponge derived carbon (NCZC/MS) composites with tunable Ni/Co ratios were synthesized by vacuum filtration and carbonization. No CNTs can be found in N2C1ZC/MS (Ni/Co ratio of 2:1) and N1C1ZC/MS composites while N1C2ZC/MS composite displays uniformly nanoparticles encapsulate in CNTs morphology. The NCZC/MS composites are made up of (Ni,Co)₃ZnC_0.7, Co₃ZnC, Ni and/or Co phases. The results show that N1C2ZC/MS composite exhibits best EMW absorption, and the minimum reflection loss (RL_min) value is -47.52 dB (2.30 mm), and the effective absorption bandwidth (EAB) is 5.01 GHz (1.40 mm). The superior EMW absorption capability is attributed to the strong magnetic loss provided by metal carbide, the interfacial polarization provided by the interfacial induction of multi-heterogeneous components and the unique spherical hollow nodules, the dipole polarization induced by N doping, the enhanced conduction loss formed by the 3D sponge skeleton, and the excellent impedance matching. Additionally, the porous structure provided by MS gives N1C2ZC/MS thermal insulation functionality. The clarify of the phase and morphology changes of the carbides by adjusting the substitution ratio Ni/Co provides insights for the design of high performances microwave absorbers.

中文翻译：

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（Ni，Co）3ZnC0.7/三聚氰胺海绵衍生碳对电磁波吸收和隔热性能的有效形貌和相调控

构建具有宽带宽和高吸收的高效电磁波 （EMW） 吸收器对于减轻电磁污染至关重要。在这里，通过真空过滤和碳化合成了具有可调 Ni/Co 比率的 （Ni，Co）₃ZnC_0.7/三聚氰胺海绵衍生碳 （NCZC/MS） 复合材料。在 N2C1ZC/MS （Ni/Co 比为 2：1） 和 N1C1ZC/MS 复合材料中找不到 CNT，而 N1C2ZC/MS 复合材料显示出均匀封装在 CNT 形态中的纳米颗粒。NCZC/MS 复合材料由 （Ni，Co）₃ZnC_0.7、Co₃ZnC、Ni 和/或 Co 相组成。结果表明，N1C2ZC/MS 复合材料表现出最佳的电磁波吸收能力，最小反射损耗（RL_min）值为-47.52 dB（2.30 mm），有效吸收带宽（EAB）为 5.01 GHz（1.40 mm）。优异的 EMW 吸收能力归因于金属碳化物提供的强磁损耗、多异质元件界面感应和独特的球形空心结节提供的界面极化、N 掺杂诱导的偶极极化、3D 海绵骨架形成的增强传导损耗以及出色的阻抗匹配。此外，MS 提供的多孔结构赋予了 N1C2ZC/MS 隔热功能。通过调整取代比 Ni/Co 来阐明碳化物的相和形貌变化，为高性能微波吸收器的设计提供了见解。