Lei Miao
,
Sakae Tanemura
,
Shoichi Toh
,
Kenji Kaneko
,
Masaki Tanemura
材料科学技术(英文)
The controlled growth of densely assembled single-phase rutile-TiO2 nanorods was demonstrated by a heating-sol-gel template process with about $\sim$300~nm in diameter and several micrometers in length. Transmission electron microscopic observation reveals these rutile-TiO2 nanorods are the aggregates of many nanocrystallites grown preferentially to the [110] zone axis direction with about 10~30 nm in diameter. The calculation and comparison of d-spacing values with those of bulk values suggest the crystal structure of nanorods close to bulk materials. Selected area electron diffraction and energy dispersive X-ray spectroscopy measurements confirm that the obtained nanorods are rutile-TiO2 nanorods with good compositional uniformity and consist of distinct shape of nanocrystallites with 10~30 nm diameter.
关键词:
Rutile-TiO2
,
null
,
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,
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,
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黄珊
,
王继刚
,
刘松
,
张玥晨
,
钱柳
,
梁杰
新型炭材料
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SiC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2 nm),并夹杂有未反应完全的石墨和SiO2。利用波长为240 nm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。
关键词:
微波法
,
碳化硅
,
纳米线
,
结构表征
,
光致发光