个人信息Personal Information
教授
博士生导师
硕士生导师
性别:女
毕业院校:大连理工大学
学位:博士
所在单位:化工学院
学科:应用化学. 精细化工. 有机化学
办公地点:大连市高新区凌工路2号西部校区化工楼E434房间
联系方式:0411-84986265
电子邮箱:zhangshf@dlut.edu.cn
Morphology control of the NaGdF4:Yb,Tm@NaGdF4 core-shell nanostructure by tailoring the ratio of core to shell
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论文类型:期刊论文
发表时间:2017-09-14
发表刊物:CRYSTENGCOMM
收录刊物:SCIE
卷号:19
期号:34
页面范围:5022-5027
ISSN号:1466-8033
摘要:Morphology control of upconversion nanoparticles (UCNPs) is of fundamental and technological importance to manipulate their shape/size-dependent properties for special applications. Here, we developed a method to control the morphology of the NaGdF4: Yb3+, Tm3+@NaGdF4 core-shell nanostructure by tailoring the ratio of precursors in the core and shell forming process. Through a core-shell approach, "flowerlike" and "sea chestnut-like" hierarchical nanostructured UCNPs have been synthesized via a thermal decomposition method. The molar ratio of core to shell is a key factor in determining the morphology of the NaGdF4: Yb3+, Tm3+@NaGdF4 core-shell nanostructure. TEM images show that the UCNPs range from 15 nm to 100 nm with sphere, hexagonal plane, and tetrahedron morphologies and flower-like aggregates were prepared by varying the precursor amount of the core while keeping the precursor amount of the shell constant. To further understand the factors affecting the morphology of the core-shell structure, the effect of the size of the core and the heating rate on the morphology of NaGdF4: Yb3+, Tm3+@NaGdF4 were also evaluated. The results indicate that when the size of the core was about 6 nm, the atomic ratio of core/shell was 0.25, and the heating rate was 10 degrees C min(-1), "sea chestnut-like" NaGdF4: Yb3+, Tm3+@NaGdF4 UCNP aggregates were formed. The selected area electron diffraction (SAED) pattern showed a ring-like pattern, indicating a polycrystal and multi-layer structure. This morphology control strategy may provide fundamental guidance for preparing hierarchical core-shell structured nanocrystals.