Lightweight Fe3C@Fe/C nanocomposites derived from wasted cornstalks with high-efficiency microwave absorption and ultrathin thickness

• Published in: Advanced composites and hybrid materials Vol. 4; no. 4; pp. 1226 - 1238
• Main Authors: Qi, Guangyu, Liu, Yuan, Chen, Lili, Xie, Peitao, Pan, Duo, Shi, Zhicheng, Quan, Bin, Zhong, Yiming, Liu, Chunzhao, Fan, Runhua, Guo, Zhanhu
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.12.2021
• Subjects: Ceramics; Chemistry and Materials Science; Composites; Glass; Materials Engineering; Materials Science; Natural Materials; Original Research; Polymer Sciences; Cornstalks; Microwave absorption; Carbon materials; Porous microstructure
• ISSN: 2522-0128; 2522-0136
• DOI: 10.1007/s42114-021-00368-0

As a typical lightweight material, carbon materials have great application prospects in fabricating microwave absorbers. In this work, the Fe 3 C@Fe/C composites with porous microstructure are obtained by a simple and environmentally friendly method with wasted cornstalks as raw materials. The reflection loss of absorbing composites reaches the minimum value which is less than −50 dB when the thickness is 1.13 mm, while widest effective absorbing bandwidth reaches 5.1 GHz when thickness is 1.50 mm. The stalk-made nanocomposites’ excellent absorbing ability is mainly credit to excellent impedance matching and attenuation characteristics of composites, which is further credit to a synergistic influence of the dielectric loss from the multiple interfaces in porous microstructure and magnetic loss from iron nanoparticles. A low-cost method to obtain microwave absorption materials and realize high-value utilization of agricultural waste to reduce pollution caused by burning cornstalks is put forward. Graphic Abstract