纳米磁性过渡金属碳化物的可控化学合成、结构及磁性研究

项目名称： 纳米磁性过渡金属碳化物的可控化学合成、结构及磁性研究

项目编号： No.51301114

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 一般工业技术

项目作者： 张雅静

作者单位： 沈阳化工大学

项目金额： 25万元

中文摘要： 纳米磁性过渡金属碳化物MxC(M=Fe,Co,Ni；x=2,3)是一种新型非稀土硬磁材料,具有广阔的应用前景。本项目拟开展MxC的可控化学合成、结构及磁性研究。申请人前期研究发现Co2C-Co3C复合纳米粒子室温矫顽力为3.1kOe，具有作为一种新型硬磁材料潜力。本项目在前期工作的基础上，系统研究合成条件对MxC纳米材料结构（物相、尺寸和形貌）的影响规律，并阐明其生长机制。控制合成参数,调节纳米MxC尺寸、晶粒取向、形貌、物相组成，以调控MxC磁性，研究其结构对磁本征性质即磁矩密度和磁晶各向异性的内在影响规律，阐明MxC矫顽力机制。构建结构与磁性关系的理论模型，采用第一原理计算方法，计算MxC的电子态密度、磁矩密度和磁晶各向异性，从结构角度深入理解其物理本质。逐步建立纳米MxC材料化学合成-结构-磁性间的科学关系，为开发新型非稀土纳米硬磁材料提供实验和理论指导。

中文关键词： 碳化物；纳米材料；磁性；热稳定性；化学合成

英文摘要： Nano-sized magnetic transition metal carbides can be potentially applied as new type non-rare-earth hard magnetic nanomaterials. In this project, investigation on the controlled chemical synthesis, structures, and magnetic properties of transition metal carbides MxC(M=Fe,Co,Ni;x=2,3) nanostructures will be performed. Our previous work showed that cobalt carbide nanoparticles exhibited higher coercivity at room temperature and could be potentially used as a new type of hard magnetic materials. Based on our previous result,transition metal carbides nanostructures, with different phases, sizes, microsturctures and magnetic properties, will be synthesized by a simple one-pot poyol reduction process. The growth mechanism of the carbides will be demonstrated. The effects of the microstructures of the carbides on the magnetic properties will be investigated based on structure and magnetic property characterization. The mechanism of coercivity of the carbides will be studied.Also, the intrinsic effects of magnetic moment density, magnetic crystalline anisotropy, size dependent, intergrain exchange coupling on the magnetic properties will be studied in detail. Based on the crystal structures, first-principles DFT-based calculations will be conducted on the transition metal carbides, the calculation of the magnetization,

英文关键词： carbides；nanomaterials；magnetic property；thermal stability；chemical synthesis