Microwave absorbing materials (MAMs) characterized by high absorption efficiency and good environmental tolerance are highly desirable in practical applications. Both silicon carbide and carbon are considered as stable MAMs under some rigorous conditions, while their composites still fail to produce satisfactory microwave absorption performance regardless of the improvements as compared with the individuals. Herein, we have successfully implemented compositional and structural engineering to fabricate hollow SiC/C microspheres with controllable composition. The simultaneous modulation on dielectric properties and impedance matching can be easily achieved as the change in the composition of these composites. The formation of hollow structure not only favors lightweight feature, but also generates considerable contribution to microwave attenuation capacity. With the synergistic effect of composition and structure, the optimized SiC/C composite exhibits excellent performance, whose the strongest reflection loss intensity and broadest effective absorption reach − 60.8 dB and 5.1 GHz, respectively, and its microwave absorption properties are actually superior to those of most SiC/C composites in previous studies. In addition, the stability tests of microwave absorption capacity after exposure to harsh conditions and Radar Cross Section simulation data demonstrate that hollow SiC/C microspheres from compositional and structural optimization have a bright prospect in practical applications.

具有高吸收效率和良好环境耐受性的微波吸收材料（MAM）在实际应用中非常受欢迎。碳化硅和碳在某些严格条件下都被认为是稳定的MAM，但它们的复合材料尽管与单体相比有所改进，但仍然无法产生令人满意的微波吸收性能。在此，我们成功地实施了成分和结构工程来制造成分可控的空心SiC/C微球。随着这些复合材料成分的变化，可以轻松实现介电性能和阻抗匹配的同时调制。中空结构的形成不仅有利于轻量化，而且对微波衰减能力也有相当大的贡献。通过成分和结构的协同作用，优化后的SiC/C复合材料表现出优异的性能，其最强的反射损耗强度和最宽的有效吸收分别达到-60.8dB和5.1GHz，其微波吸收性能实际上优于传统的SiC/C复合材料。以往研究中大多数 SiC/C 复合材料。此外，恶劣条件下微波吸收能力的稳定性测试和雷达截面模拟数据表明，成分和结构优化的空心SiC/C微球在实际应用中具有广阔的前景。