氮化硼包覆碳化硅纤维表面CVD法生长碳纳米管研究  

Growth of Carbon Nanotubes on the Surface of Boron Nitride Coated Silicon Carbide Fibers Based on the CVD Method

作　　者：闫兵 岳建岭 邹杨君 楼嘉伟 杜作娟 刘愚 黄小忠[1] YAN Bing;YUE Jianling;ZOU Yangjun;LOU Jiawei;DU Zuojuan;LIU Yu;HUANG Xiaozhong(Powder Metallurgy Research Institute,Central South University,Changsha 410083,China;School of Electrical and Electronic Engineering,Harbin University of Science and Technology,Harbin 150006,China)

机构地区：[1]中南大学粉末冶金研究院,长沙410083 [2]哈尔滨理工大学电气与电子工程学院,哈尔滨150006

出　　处：《表面技术》2024年第12期218-229,239,共13页Surface Technology

基　　金：国家自然科学基金青年基金(52002403)。

摘　　要：目的通过调节化学气相沉积(CVD)的工艺参数,实现碳纳米管(CNTs)在氮化硼(BN)包覆的碳化硅纤维(SiCf)表面的可控生长。方法通过控制单一变量,采用扫描电子显微镜、热重分析、X射线光电子能谱等表征手段,系统地研究了CVD工艺参数和BN表面改性对CNTs形貌、长度、含量的影响。结果通过改变CVD工艺参数,实现了对CNTs形貌、长度、含量的调节与控制,获得了CNTs和BN协同改性的SiC纤维(SiC@BN-CNTs)。其中,SiC@BN-OH在反应温度为700℃、反应时间为20 min等参数下具有最大的CNTs产率(质量分数为10.6%),且形貌良好、含量较高。结论浸渍催化剂和缩短碳源与载体的距离对生长CNTs有积极影响,增加了CNTs的长度和生长密度;通过调节反应温度和时间能够实现对CNTs长度、含量的精确控制,从而获得高质量、高结晶度的CNTs;在反应器中,气体和催化剂的含量相互影响,在制备过程中需要考虑气体和催化剂的比例,按比例同时增加气体和催化剂的流入速率能够获得更好的结果。BN表面羟基化改性处理增强了BN对催化剂的吸附,促进了催化剂颗粒的分散,提高了CNTs的产率。The optimization of the interfacial layer plays a very critical role in the improvement of the mechanical properties(especially toughness)of silicon carbide fiber/silicon carbide(SiCf/SiC)composites.Hexagonal boron nitride(h-BN)is a common interfacial phase for SiCf/SiC composites,and carbon nanotubes(CNTs)are also popular reinforcing materials for the composites.The work aims to achieve the controlled growth of carbon nanotubes on the surface of boron nitride coated silicon carbide fibers by adjusting the process parameters in chemical vapor deposition(CVD).The effects of chemical vapor deposition conditions,such as impregnation catalyst condition,reaction temperature,reaction time,gas inflow rate,catalyst inflow rate,and BN surface modification,on the morphology,length,and content of CNTs grown on BN-coated silicon carbide fibers were systematically investigated by controlling a single variable and applying characterization means such as scanning electron microscopy,thermogravimetric analysis,and X-ray photoelectron spectroscopy.By changing the process parameters,the morphology,length,and content of CNTs were adjusted and controlled to obtain CNTs and BN modified silicon carbide fibers(SiC@BN-CNTs).The results showed that the impregnated catalyst could release more Fe catalyst particles in situ on the BN surface,which improved the yield of CNTs,but led to the uneven distribution of Fe particles and aggravated agglomeration phenomenon,making the distribution of CNTs uneven and the diameter coarse and fine.Shortening the distance between the carbon source and the substrate in the tube furnace could increase the length and content of CNTs,which was positive for substrates that were not easy to grow CNTs.The reaction temperature strongly affected the content and length of CNTs.The higher the temperature,the higher the activity of the catalyst particles,the higher the length and content of CNTs,and the more pyrolytic carbon(PyC),leading to the array-like CNTs on the surface.Adjusting the reaction time could control

关 键 词：六方氮化硼 碳纳米管 化学气相沉积 工艺参数 氮化硼羟基化 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TQ127.11[化学工程—无机化工]