碳包裹氮化铁复合材料的制备及微波吸收性能  

Preparation and microwave absorption properties of carbon-coated iron nitride composites

作　　者：王文敬 董浩琪 卢洁 李伟 朱磊 郭立升 张成华 魏宇学 孙松 WANG Wenjing;DONG Haoqi;LU Jie;LI Wei;ZHU Lei;GUO Lisheng;ZHANG Chenhua;WEI Yuxue;SUN Song(School of Chemistry and Chemical Engineering,Anhui University,Hefei 230601,China;School of Materials Science and Engineering,Anhui University,Hefei 230601,China;Anhui Tanxin Technology Co.,Ltd.Huaibei,235141,China)

机构地区：[1]安徽大学化学化工学院,安徽合肥230601 [2]安徽大学材料科学与工程学院,安徽合肥230601 [3]安徽碳鑫科技有限公司,安徽淮北235141

出　　处：《中国粉体技术》2024年第3期39-50,共12页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:21902001,22179001,22102001;安徽省高校杰出青年科研项目,编号:2022AH020007;安徽高校协同创新项目,编号:GXXT-2023-009;安徽省高等学校自然科学基金项目,编号:2023AH050114。

摘　　要：【目的】研究不同氮化铁复合材料Fe_(2)N@C、Fe_(3)N@C和Fe_(4)N@C的微波吸收性能。【方法】通过水热法合成金属有机骨架材料(MOFs),经过氮化处理得到Fe_(2)N@C、Fe_(3)N@C和Fe_(4)N@C复合材料;采用X射线衍射(X-ray diffraction,XRD)、超高分辨扫描电子显微镜(scanning electron microscope,SEM)、高分辨透射电子显微镜(transmission electron microscope,TEM)、拉曼光谱(Raman spectra,Raman)和X射线光电子能谱(X-ray photoelectron spectroscopy,XPS)等技术表征、定性Fe_(2)N@C、Fe_(3)N@C和Fe_(4)N@C的结构、形貌以及成分变化,结合矢量网络分析(vector network analyzer,VNA)和振动样品磁强计(vibrating sample magnetometer,VSM)定量分析Fe_(2)N@C、Fe_(3)N@C和Fe_(4)N@C对微波的反射损耗能力以及磁性能。【结果】Fe_(2)N@C和Fe_(4)N@C因介电常数远大于磁导率,导致阻抗匹配失衡,而Fe_(3)N@C介电常数和磁导率相近,存在较好的阻抗匹配,涂层厚度为2 mm的样品,小于反射损耗为−10 dB的有效吸波宽带达到的频率为2.4 GHz,在频率为9.1 GHz处最小的反射损耗为−14.1 dB。【结论】3种氮化铁的相结构和碳层的缺陷程度不同,氮化铁核与碳壳的导电性不同,会在界面间出现电荷聚集,引起界面极化,导致Fe_(2)N@C和Fe_(4)N@C的介电常数增大,使得Fe_(2)N@C和Fe_(4)N@C中的介电常数远大于磁导率,最终导致阻抗匹配失衡,具有较差的吸波性能。Objective The energy attenuation of wave-absorbing materials primarily occurs through two mechanisms:dielectric loss and magnetic loss.Conventional wave-absorbing materials are less effective because they cannot simultaneously use both electrical and magnetic losses to attenuate microwave interference.Iron nitride,characterized by magnetic properties,such as high satura⁃tion magnetization,low density,large surface area,and environmental friendliness,has applications in various high-tech fields.However,its widespread use is limited due to its poor dielectric loss characteristics.Carbon materials,known for their exceptional conductivity and dielectric loss properties,can be combined with iron nitride to form composite materials that exhibit both magnetic and high dielectric losses.To achieve this,metal-organic frameworks(MOFs)are used as precursors for the syn⁃thesis of Fe_(2)N@C,Fe_(3)N@C and Fe_(4)N@C through a process involving calcination and nitriding.These core-shell wave-absorbing materials exhibit excellent stability.The incorporation of carbon increases the dielectric loss of iron nitride,generating compos⁃ites that exhibit high dielectric and magnetic losses,thereby improving the microwave absorption of Fe_(2)N@C,Fe_(3)N@C,and Fe_(4)[e-mail] investigations will explore the microwave absorption variations between different compositions of Fe_(2)N@C,Fe_(3)N@C,and Fe_(4)[e-mail] The physical composition of Fe_(2)N@C,Fe_(3)N@C,and Fe_(4)N@C was analyzed using X-Ray diffraction(XRD).Their micro-morphology was analyzed using ultra-high-resolution scanning electron microscopy(SEM)and high-resolution transmis⁃sion electron microscopy(TEM).The micro-morphology of Fe_(2)N@C,Fe_(3)N@C,and Fe_(4)N@C was determined through the suc⁃cessful synthesis of carbon-encapsulated iron nitride.Raman spectroscopy and X-ray photoelectron spectroscopy(XPS)were also employed for this purpose.XPS techniques were used to characterize and investigate their conformational relationships.Microwave absorption properties,as

关 键 词：氮化铁 复合材料 阻抗匹配 微波吸收 

分 类 号：TM25[一般工业技术—材料科学与工程] TB4[电气工程—电工理论与新技术]