High-performance electromagnetic wave absorption materials constitute key components of microelectronic devices. Traditional absorbents possess magnetic losses and/or dielectric losses, while the experimental approach for their simultaneous enhancement is still lacking. Here, we demonstrate that the core/shell structural Ni@C nanocapsules, functionalized by atomic-scale oxygen substitutions that can be formed catalytically by highly defective graphitic structure, present enhanced dielectric loss capacities at gigahertz. In particular, >90% of the microwave energy could be attenuated for a planar absorber with a thickness down to 1–1.5 mm at 7.6–13.8 GHz. Experimental characterizations coupled with density functional theory calculations further evidence that the capacity enhancement is ascribed to the structure breaking at the heterogeneous substitutional zones, resulting in the intrinsic polarization of carbon–oxygen heterostructures. The present study shows a new mentality of designing for optimizing electromagnetic wave absorption materials and also has pointed out the atomic-scale structural origin of the electromagnetic response performance.

中文翻译：

---

具有原子级氧取代的核壳纳米胶囊中增强的高频微波吸收

高性能电磁波吸收材料构成微电子器件的关键部件。传统的吸收剂具有磁损耗和/或介电损耗，而同时增强它们的实验方法仍然缺乏。在这里，我们证明了核/壳结构的 Ni@C 纳米胶囊，通过原子级氧取代功能化，可以由高度缺陷的石墨结构催化形成，在千兆赫兹表现出增强的介电损耗能力。特别是，对于厚度低至 1-1.5 毫米的平面吸收器，在 7.6-13.8 GHz 时，>90% 的微波能量可以衰减。结合密度泛函理论计算的实验表征进一步证明，容量增强归因于异质置换区的结构破坏，导致碳-氧异质结构的内在极化。本研究展示了一种优化电磁波吸收材料的设计思路，也指出了电磁响应性能的原子级结构起源。