ZnS量子点/聚氨酯纳米复合材料的荧光光谱  

Fluorescence Spectra of Zinc Sulfide Quantum Dots/Polyurethane Nano-Composite

作　　者：李光吉[1] 黄玉刚[1] 朱祖钊[2] 罗伟昂[2] 陈旭东[2] 

机构地区：[1]华南理工大学材料科学与工程学院,广东广州510640 [2]中山大学化学与化学工程学院,广东广州510275

出　　处：《华南理工大学学报（自然科学版）》2009年第3期1-5,共5页Journal of South China University of Technology(Natural Science Edition)

基　　金：广东省科技攻关项目(2007B010600046)

摘　　要：采用水相法制备了经巯基丙酸表面改性的ZnS量子点溶胶,再利用铸膜法得到了ZnS量子点/聚氨酯纳米复合膜.通过紫外吸收光谱和荧光光谱等方法对制得的ZnS量子点及ZnS量子点/聚氨酯纳米复合膜进行了分析表征.紫外吸收光谱表明,纯化前后ZnS量子点的尺寸没有变化,根据Brus模型可知,70℃下回流得到的ZnS量子点的尺寸为3.0 nm.荧光光谱表明:提高回流温度可显著提高ZnS量子点的发光强度;ZnS量子点水溶液在400 nm左右的发光带是受限态发光,归因于ZnS量子点表面锌原子空位产生的载流子辐射再结合;复合后发光带从400 nm红移到425 nm左右.ZnS quantum dots （QDs） sol surface-modified by mercaptopropionic acid （MPA） was prepared via the aqueous-phase method, and ZnS QDs/polyurethane nano-composite membrane was prepared via film casting. Then, ZnS QDs and the prepared nano-composite membrane were characterized by UV-Vis absorption spectra and fluorescence spectra. UV-Vis absorption spectra show that the size of ZnS QDs, which is 3.0nm at the reflux temperature of 70 ℃ according to the Brus model, keeps unchanged after the purification. Fluorescence spectra show that the increase of reflux temperature results in a great improvement of fluorescence intensity of ZnS QDs, that the emission band of ZnS QDs in water at about 400 nm attributes to the trapped emission arising from the radiative recombination of the trapped carriers caused by the Zn vacancies on QDs surface, and that the emission band of ZnS QDs after the recombination exhibits a redshift from 400 nm to 425 nm.

关 键 词：硫化锌 量子点 聚氨酯 复合材料 荧光光谱 

分 类 号：O631[理学—高分子化学]