SiC@Fe3O4@C轻质纳米复合吸波材料的设计、性能调控及机理研究

Recently, SiC one-dimensional (1D) nanomaterials have attracted much attention from researchers since its high performance in the field of electromagnetic wave absorption. It is still a challenging and urgent research topic to design and prepare the SiC based lightweight nanocomposite absorbing material with corrosion resistance, oxidation resistance and excellent wave absorption properties, and to explore the basic theories of growth and the performance adjustment. . In this project, mass production SiC nanowire is employed as the carrier, and the design, performance adjustment and basic theory of the SiC@Fe3O4@C lightweight nanocomposites absorbing material are studied. The main research contents include: 1) The surface of the SiC nanowire is decorated by Fe3O4 nanoparticles and C coating through a variety of process. Series of SiC@Fe3O4@C 1D nanocomposites with controlled morphology, microstructure and composite and corresponding key production technology are obtained. 2) On the basis of systematic characterization, combining with the basic theory of nucleation and growth of different components (Fe3O4 and C), the preparation mechanism of SiC@Fe3O4@C 1D nanocomposites is revealed, and the corresponding theoretical model is established. 3) To obtain the electromagnetic properties with strong absorption, wide band, adjustable by building the linkages between as-synthesized products and electromagnetic parameters. Combaining with the electromagnetic wave absorption theories, a property adjustment mechanism is illustrated under the synergistic action of dielectric loss and magnetic loss.

近年来，SiC一维纳米材料在吸波领域的优异表现已引起研究人员的广泛关注。设计并制备具有耐腐蚀、抗氧化、吸波性能优异的SiC基轻质纳米复合吸波材料，探究其生长与性能调控机理，成为一项亟待解决的研究课题。. 本项目以量产化制备的 SiC纳米线为基体材料，创新性地开展SiC@Fe3O4@C轻质纳米复合吸波材料的设计、性能调控及机理研究。主要研究内容包括：1）通过调整工艺参数，在SiC纳米线表面分步复合Fe3O4纳米颗粒与碳质包覆层，获得产物形貌、微观结构、组成可控的系列SiC@Fe3O4@C一维纳米复合材料及其可控制备技术；2）在系统表征的基础上，结合各组元的形核-生长理论，诠释SiC@Fe3O4@C一维纳米复合材料的生长机理；3）建立制备产物与电磁参数之间的内在联系，获得具有强吸收、宽频带、可调控等特点的电磁吸波性能，结合电磁波吸收理论，建立介电损耗与磁损耗协同作用下的性能调控机理。

基于电磁辐射对生物体与精密仪器、信息安全造成的巨大危害，研究轻质纳米复合吸波材料降低电磁波影响的紧迫性和必要性，本项目以量产化SiC纳米线为基体，分别采用水热-碳化法与包覆热分解法依次与磁性Fe3O4纳米颗粒、非晶碳外壳复合，成功制备出SiC@Fe3O4@C一维纳米复合材料，从晶体生长、异质成核等理论出发，诠释了产物的形核-生长过程，提出了合理的生长机理模型；根据大量测试表征结果，系统研究了产物形貌（Fe3O4颗粒尺寸及分布密度、非晶碳层厚度等）、结构组成（Fe3O4结晶状态、复合材料组分、成键形式等）、表面界面状态等与产物电磁参数之间的内在联系，并获得了产物在不同匹配厚度、不同频率下电磁吸波性能的影响规律，实现了对其吸波频率和吸波频带宽度的调控；研究表明：水热-碳化法制备优选产物在匹配厚度为1.79 mm时，于12.82 GHz处获得最强反射损耗为-48.20 dB，其相应的有效吸收频带宽度为4.48GHz；采用包覆热分解法制备出的优选SiC@Fe3O4@C一维纳米复合材料在1.95mm匹配厚度时，最强反射损耗达-67.922dB，相应的有效吸收频带宽度为4.96GHz；结合极化弛豫、多重散射、磁滞损耗、涡流损耗等理论，系统研究了介电损耗与磁损耗双重机制作用下产物的电磁吸波性能优化的协同机理，建立了合理的反射损耗模型，为SiC基纳米复合材料的开发提供了理论支持。. 在本项目完成过程中，先后获青岛市自然科学一等奖1项，中国石油化工联合会科技进步二等奖/三等奖各1项；获授权国家发明专利6项，授权实用新型专利1项；发表SCI论文14篇，JCR Q1区13篇，影响因子大于6的论文9篇，（其中第一/通讯(含共同)作者10篇），远超过项目计划书中任务指标。所获得的原创性成果达到国内外同类技术的领先水平。