甲烷吸附和碳原子热扩散规律对三维网状石墨烯生长均匀性及其热导率影响的研究

项目名称： 甲烷吸附和碳原子热扩散规律对三维网状石墨烯生长均匀性及其热导率影响的研究

项目编号： No.51506012

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 能源与动力工程

项目作者： 唐波

作者单位： 常州大学

项目金额： 20万元

中文摘要： 石墨烯有望取代传统材料在热输运领域发挥重要作用。采用化学气相沉积制备三维网状石墨烯已引起科学界的广泛关注,但其生长过程中的关键热科学问题没有得到系统研究。本课题将围绕高温条件下，泡沫镍表面甲烷吸附、裂解及后续碳原子扩散制备三维网状石墨烯的传质过程开展研究。探究甲烷和氢气对衬底表面有效吸附位的竞争规律；阐明反应温度和气氛比例对此竞争吸附的影响规律；揭示衬底表面甲烷覆盖率对三维网状石墨烯厚度均匀性及热导率的影响。进一步研究反应时间、衬底降温速率对碳原子传质的影响规律，实现碳原子扩散的均匀性及速率的合理性；揭示碳原子扩散对三维网状石墨烯层数的影响。采用扫描电子显微镜、透射电子显微镜和拉曼光谱等对产物进行均匀性和层数表征；采用激光热导仪和差示扫描量热仪测试计算产物的热导率。本课题将揭示三维网状石墨烯生长的基本传质规律，完善其生长动力学，指导厚度均匀、层数可控且具有高热导率的三维网状石墨烯的制备。

中文关键词： 三维网状石墨烯；甲烷吸附；碳原子扩散；生长动力学；热导率

英文摘要： As one of new nano-materials, graphene has the potential to replace traditional materials and play a momentous role in the heat transport area. Preparing three-dimensional graphene networks (3DGNs) by chemical vapor deposition method has attracted more and more attention. However, some key scientific issues on the formation of the 3DGNs have not been will-researched. This project will focus on the mass transfer process during the growth of the 3DGNs from decomposition of methane on surface of foam nickel (FN) under high temperature. Reveals the competition mechanism of methane and hydrogen on the effective adsorption sites of the FN, and illuminates the law of the influence on this competition from temperature and composition of the reaction atmosphere. According to the above research, relationship between uniformity of the 3DGNGs and coverage of the methane molecular on the NF will be revealed, which is crucial to prepare the 3DGNGs with homogeneous thickness. Moreover, the mass transfer law of carbon atoms will be studied, and the influences on the thickness of the 3DGNs from reaction time and cooling rate of substrate will be promulgated. Homogeneous thermal diffusion of carbon atoms can be realized based on optimizing cooling rate of the substrate, which is benefit to achievement the growth of the 3DGNs with controlled number of layers. Scanning electron microscopy, Transmission electron microscopy, Atom forces microscopy and Raman spectra will be adopted to analyze the morphology, thickness and quality of the 3DGNs. Laser flash analysis and differential scanning calorimetry were used to measure and calculate the thermal conductivity of the 3DGNs, and this parameter will be employed as an important criterion to judge the quality of product. The findings of this project reveal the fundamental law of the 3DGNs growth, which can be used to guide the preparation of the 3DGNs with controlled thickness and high quality.

英文关键词： three-dimensional graphene networks;methane adsorption;carbon atoms diffusion ;growth kinetics ;thermal conductivity