Co/CeO 2 /C composites derived from bimetallic metal–organic frameworks for efficient microwave absorption

• Published in: Dalton transactions : an international journal of inorganic chemistry 2023-09, Vol.52 (36), p.12632-12645
• Main Authors: Yao, Zhiqian, Xu, Suqiong, Zhang, Xianke, Zhu, Jiawei, Liao, Peng, Yuan, Jujun, Rong, Chuicai, Liu, Xiaoqing, Xiong, Zuzhou, Kang, Shuying, Kuang, Fangguang
• Format: Article
• Language: English
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/D3DT02036C

CeO 2 , an n-type semiconductor material, has been widely used in microwave absorption (MA) due to its unique structural features such as oxygen vacancies and interstitial atoms. In this paper, Co/CeO 2 /C composites were prepared by a hydrothermal method followed by a pyrolysis process. The effect of different pyrolysis temperatures (650–950 °C) on the MA property of the composites was investigated. When the pyrolysis temperature was 850 °C, the Co/CeO 2 /C-850 composite exhibited outstanding MA behavior in the frequency range of 2–18 GHz, displaying a minimum reflection loss (RL min ) of −45.22 dB and an effective absorption bandwidth (EAB) of 4.61 GHz at a thin thickness of 1.75 mm. The MA performance of the Co/CeO 2 /C composites is mainly attributed to the dielectric loss due to interfacial polarization originating from different interfaces and dipole polarization caused by the oxygen vacancies in CeO 2 . In addition, the introduction of Co nanoparticles not only provides the magnetic loss but also modulates impendence matching for the current magnetoelectric coupling system.