ABSTRACT MCo2O4 (M = Mn,Ni) microparticles were synthesised by a simple hydrothermal solvothermal method. The samples were characterised by X-ray diffraction, X-ray energy dispersive spectroscopy and scanning electron microscopy, which showed that MnCo2O4 microparticles with spherical particles aggregated by a large number of small cubes and cubic shaped NiCo2O4 microcubes were obtained. The microwave absorption properties of these products were systematically investigated by vector network analysis. Results indicated that the minimum reflection loss value of MnCo2O4 microparticles was −26.34 dB at 11.04 GHz with the absorber thickness of 2.5 mm, which was much lower than that of NiCo2O4 microcubes with the same absorber thickness. The possible mechanism was analysed, indicating that the geometry and size of MCo2O4 (M = Mn,Ni) microparticles played a key role in microwave absorption.

中文翻译：

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MCo2O4 (M = Mn, Ni) 微粒的水热溶剂热合成和微波吸收研究

摘要 MCo2O4 (M = Mn,Ni) 微粒是通过简单的水热溶剂热法合成的。对样品进行X射线衍射、X射线能谱和扫描电镜表征，结果表明得到了球形颗粒由大量小立方体聚集而成的MnCo2O4微粒和立方形NiCo2O4微粒。通过矢量网络分析系统地研究了这些产品的微波吸收特性。结果表明，吸收体厚度为2.5 mm时，MnCo2O4微粒在11.04 GHz下的最小反射损耗值为-26.34 dB，远低于吸收体厚度相同的NiCo2O4微立方​​体。分析了可能的机制，表明 MCo2O4 (M = Mn,