Kim Jong-Uk, Lee Jong-Jin, Jang Ho Seong, Jeon Duk Young, Yang Heesun
Department of Materials Science and Engineering, Hongik University, Seoul 121-791, Korea.
J Nanosci Nanotechnol. 2011 Jan;11(1):725-9. doi: 10.1166/jnn.2011.3193.
The widely tunable emissions of Zn(x)Cd(1-x)Se alloy quantum dots (QDs), which emit green to red wavelengths from 534 to 620 nm, are reported. Green-, yellow-, orange-, and red-emitting QDs were synthesized by varying a point of time for oleylamine (as a co-surfactant) addition and a Se precursor amount, and keeping a constant Zn/Cd precursor ratio. With reaction time the alloying and particle growth of the alloy QDs progressed simultaneously in the opposite direction in the variation of their band gap. However, the band gap energies of all QDs were observed to be gradually blue-shifted due to the slight dominance of alloying over the particle growth effect. The compositions of alloy QDs were estimated based on their sizes and band gap energies. Zn(x)Cd(1-x)Se core QDs were also overcoated with a ZnSe shell with a higher band gap to enhance their quantum yields.
据报道，Zn(x)Cd(1-x)Se合金量子点（QDs）具有广泛可调谐的发射特性，其发射波长范围为534至620纳米，涵盖绿色到红色波段。通过改变油胺（作为共表面活性剂）添加时间点和硒前驱体的量，并保持锌/镉前驱体比例恒定，合成了发射绿色、黄色、橙色和红色光的量子点。随着反应时间的推移，合金量子点的合金化和颗粒生长在其带隙变化中以相反方向同时进行。然而，由于合金化在颗粒生长效应上略有优势，所有量子点的带隙能量均观察到逐渐蓝移。基于合金量子点的尺寸和带隙能量估算了其组成。Zn(x)Cd(1-x)Se核量子点还被包覆了具有更高带隙的ZnSe壳层，以提高其量子产率。
