Several composites of modified graphitic carbon nitride (MCN) and Fe₃O₄ particles were obtained through pyrolysing MCN/iron acetylacetone (Fe(acac)₃) at different temperatures to form electromagnetic wave (EWM) absorbers. By decreasing the nitrogen content of g-C₃N₄ and introducing Fe₃O₄ particles, the EMW absorption ability of the g-C₃N₄ derivatives (MCN/Fe₃O₄) improved remarkably. For MCN/Fe₃O₄-500 with 6 wt% filling, the minimum reflection loss (RL_min) reached −73.93 dB at a thickness of 3.4 mm and the effective absorption bandwidth (EAB) was as high as 5.44 GHz at a thickness of 1.9 mm. Additionally, the mass ratio of MCN and Fe₃O₄ and the EMW absorption mechanism of MCN/Fe₃O₄-500 were also discussed. This study provides a new approach for the preparation of high-efficiency EMW absorbers by modification of g-C₃N₄.

中文翻译：

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一种改性石墨氮化碳 (MCN)/Fe3O4 复合材料作为超电磁波吸收剂

通过在不同温度下热解MCN/乙酰丙酮铁(Fe(acac) ₃ )形成电磁波(EWM)吸收体，获得了几种改性石墨氮化碳(MCN)和Fe ₃ O ₄颗粒的复合材料。通过降低gC ₃ N ₄的氮含量并引入Fe ₃ O ₄颗粒，gC ₃ N ₄衍生物（MCN/Fe ₃ O ₄）的EMW吸收能力显着提高。对于填充量为 6 wt% 的MCN/Fe ₃ O ₄ -500，最小反射损耗 (RL _min) 在厚度为 3.4 mm 时达到 -73.93 dB，有效吸收带宽 (EAB) 在厚度为 1.9 mm 时高达 5.44 GHz。此外，还讨论了MCN与Fe ₃ O ₄的质量比以及MCN/Fe ₃ O ₄ -500的EMW吸收机理。该研究为通过修饰gC ₃ N ₄制备高效EMW 吸收剂提供了一种新方法。