微波法合成SiC纳米线及其光致发光性质  

Structural characterization and photoluminescence properties of SiC nanowires prepared by microwave method

作　　者：黄珊[1,2] 王继刚[1,2,3] 刘松[1,2] 张玥晨 钱柳[1] 梁杰[1] 

机构地区：[1]东南大学材料科学与工程学院江苏省先进金属材料重点实验室,江苏南京211189 [2]东南大学-张家港工业技术研究院,江苏张家港215628 [3]西藏民族大学,陕西咸阳712082

出　　处：《新型炭材料》2015年第3期230-235,共6页New Carbon Materials

基　　金：新世纪优秀人才支持计划;西藏自治区重点科技项目;江苏省"青蓝工程"(NCET-12-0119);"六大人才高峰"(2013-JY-007)~~

摘　　要：以Si粉、SiO2粉和人造石墨为原料,在1480℃、4 kW、80 min的真空微波辐照条件下快速高效地合成SiC纳米线。利用SEM、TEM、XRD等对所得产物的微观结构解析表明,在未使用催化剂的条件下,基于气固（VS）机制可成功制备出β型SiC。根据坩埚中的部位不同,所得Si C呈现出不同的形貌。坩埚上层的产物呈亮绿色,较为纯净,主要为直径约150 nm的纳米棒,并含有部分微米级SiC晶粒,表面氧化迹象不明显。其余部分产物呈灰绿色,主要是直径为20~50 nm的SiC/SiO2同轴纳米线（表层的SiO2厚度约2nm）,并夹杂有未反应完全的石墨和SiO2。利用波长为240nm的激发光分别对SiC纳米棒和同轴纳米线的光致发光特性的测试表明,两者均可观察到峰位在390 nm左右的发射峰,此结果与所报道的β-SiC纳米材料的发光性能相比,蓝移程度更高。SiC nanowires were synthesized by a microwave-heating method at 1480 ℃ for 80 rain under vacuum, using silicon powder, silica dioxide powder and artificial graphite as raw materials. SEM, TEM and XRD were used to investigate the microstruc- ture of the samples and excitation light with wavelength of 240 nm was used to test the photoluminescence properties of the products. Results indicated that-βSIC can be synthesized directly without using a catalyst by the vapor-solid growth mechanism. The samples exhibited different morphologies and sizes at different zones due to the temperature differences. The products in an upper crucible were bright-green, relatively pure SiC, consisting of mainly nano-rods with a diameter of about 150 nm and small amount of SiC micro-crystals, and surface oxidation was not obvious. The products in other zones were grey-green with lots of SiC/SiO2 coaxial nanowires with a diameter around 20-50 nm and a SiO2 surface layer of thickness about 2 nm, and there was also some un-reacted graphite and silica dioxide. Both the SiC nano-rods and SiC/SiO2 coaxial nanowires exhibited a strong broad photoluminescence peak at a wavelength of about 390 nm and a high degree of blue-shift compared with the reported luminescence of βSIC nano-mate- rials.

关 键 词：微波法 碳化硅 纳米线 结构表征 光致发光 

分 类 号：TB383.1[一般工业技术—材料科学与工程] TQ163.4[化学工程—高温制品工业]