CdSe/CdS核壳型量子点的合成及性质研究

Synthesis and Characterizing of the Core-shell CdSe/CdS Quantum Dots

在三相体系中合成了核壳型CdSe/CdS量子点。在三相体系中,油酸和乙醇的混和物组成液相(L),油酸钠为固相(S),Cd2+溶液和乙醇组成溶液相(S)。量子点在两相的界面形成。所制备的量子点用TEM、XRD和FL进行表征。结果表明,量子点的粒径分布均匀,形貌规则,为立方型晶体。在核表面包覆上宽带隙的半导体后,其光量子产率极大提高,表明核的表面缺陷被消除。

In this paper, the core - shell quantum dots CdSe/CdS （QDs） were synthesized via three - phase system. The system was consisted of the mixture of oleic acid and alcohol（ liquid phase）, sodium oleate（ solid phase） and the mixture of the alcohol and Cd2 ＋ solution （ solution phase） , the QDs were formed at the interface of the phases. The assynthesized QDs were characterized by the TEM, XRD and the FL. The showed that the QDs were narrow sized distribution, uniform morphology and cubic crystal structure. The quantum yield of the CdSe was greatly enhanced by covering a layer of CdS on the surface, which showed that the surface defects of the CdSe were mostly eliminated by formation of the CdS shell.