催化剂、温度和保护气体对微硅粉合成碳化硅晶须的影响  

Effect of Catalysts,Temperature and Protective Gas on Formation of Silicon Carbide Whiskers from Silica Fume

作　　者：李青翠 陆俊宇 张鹏 LI Qing-cui;LU Jun-yu;ZHANG Peng(College of Chemistry and Bioengineering,Hechi University,Yizhou 546300,China)

机构地区：[1]河池学院化学与生物工程学院

出　　处：《人工晶体学报》2019年第7期1365-1371,共7页Journal of Synthetic Crystals

基　　金：广西高校中青年教师基础能力提升项目(KY2016YB387);河池学院博士启动项目(XJ2015KQ012)

摘　　要：以工业废弃物微硅粉为硅源,石墨为碳源,硼酸为催化剂,采用碳热还原法制备碳化硅晶须。通过XRD及SEM对合成产物的物相及形貌进行分析,探讨了碳源、合成温度、催化剂加入量和保护气体对合成碳化硅晶须的影响。结果表明:选择石墨为碳源可成功制备出碳化硅晶须;合成温度为1550℃和1650℃时,所制备的晶须呈直线状,表面平直光滑,而当温度为1600℃时,晶须呈竹节状;以氮气为保护气体,催化剂的含量为5%~6%时,合成的晶须的产率最高,且品质好,晶须在氮气中的生长机理推测为气固机理。该合成方法为工业废弃物微硅粉的高质化利用提供了一条切实可行的路线。The present work describes an economical and simple synthesis strategy for the fabrication of SiC whiskers using industrial waste product.Carbothermal reduction route is used for the reduction of silicon dioxide from the silica fume in the presence of suitable catalyst.It has been observed that the growth rate and product morphology are significantly affected by the process temperature,catalyst and inert gas.It is found that SiC whiskers can be successfully synthesized by using graphite as carbon source.The as-synthesized SiC whiskers are smooth,straight and long at 1550℃or 1650℃.However,they have bamboo-like morphology at temperature of 1600℃.The products quality is good and the yield is high when the content of catalyst is 5%-6%and N 2 is used as protective gas.The tentative growth mechanism is vapor-solid mechanism.This synthesis strategy is resourceful in utilizing the industrial waste product silica fume.

关 键 词：微硅粉 碳热还原反应 碳化硅晶须 生长机理 

分 类 号：O784[理学—晶体学]