摘要
采用醋酸锌、醋酸镧和硫代乙酰胺(TAA)为原料,水热合成法制备了粒度分散均匀的镧掺杂硫化锌纳米晶。粉末X-射线衍射(XRD)和透射电子显微镜(TEM)测试结果表明合成的样品为立方闪锌矿结构;纳米晶为近球形的多晶粒子,平均粒径在25nm左右且分布较窄。从纳米晶紫外-可见(UV-vis)光谱数据计算的半导体带宽(Eg)相对于体相材料有较大的蓝移,表现出明显的量子尺寸效应。用荧光光谱(PL)研究了ZnS:La纳米晶的光致发光能力,结果表明产物的荧光发射峰位于465nm左右,且具有良好的发光性能。此外,通过改变镧的掺杂量和反应的时间来研究发光强度的变化,随着掺杂量的提高和反应时间的延长,纳米晶的发光强度都呈现出先增强后减弱的趋势,并对具体原因进行了探讨。
ZnS： La nanocrystals were directly synthesized in hydrothermal condition by using Zn（CH3COO）2· 2H2 O, La（CH3 COO）3·5H20 and CH3 CSNH2 as main sources. The XRD and TEM experimental results showed that as --prepared approximately spherical ZnS： La nanoparticles had a cubic zinc blende structure and narrow size distribution with average diameter at about 25nm. The particle diameter calculated using the Scherer＇s formula was 4. 9nm which indi- cated nanoparticles had polycrystalline structure. From spectrum data of UV-vis characterization, the calculated band gap of nanocrystals was 3.86ev which was blue shifted from that of bulk materials（3.66ev） and confirmed quantum size effect of nanocrystals. The optical properties of nanocrystals were determined by using photoluminescence（PL） spectrua,and it was shown that the products exhibited good optical properties and maximum emission peak was at about 465nm. In addition, the change of intensity of photoluminescence was investigated by varying the reaction time and concentration of La doped in ZnS matrix The intensity of luminescence first increased then decreased with increase of reaction time and concentration of La and the detailed mechanism was discussed.
出处
《化工新型材料》
CAS
CSCD
北大核心
2012年第12期107-109,共3页
New Chemical Materials
基金
平顶山学院高层次人才资助项目(2008008)
关键词
ZNS
La纳米晶
水热
荧光光谱
光学性能
ZnS： La nanocrystal, hydrothermal, photoluminescence, optical property
作者简介
张丽（1979-），女，硕士，讲师，主要从事材料化学方面研究。
