School of Materials Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China.
J Colloid Interface Sci. 2011 Feb 1;354(1):15-22. doi: 10.1016/j.jcis.2010.10.013. Epub 2010 Oct 12.
A low-cost, green, and reproducibly non-injection one-pot synthesis of high-quality CdS quantum dots (QDs) is reported. The synthesis was performed in the open air by mixing precursors cadmium stearate and S powder into a new solvent N-oleoylmorpholine. An overlapped nucleation-growth stage followed by a dominated growth stage was observed. The resulting QDs exhibited well-resolved absorption fine substructure and a dominant band-edge emission with a narrow size distribution (the full width at half maximum (fwhm) was only 22-24nm). The maximum photoluminescence (PL) quantum yield (QY) was as high as 46.5%. Highly monodispersed CdS QDs with tunable sizes and similar PL fwhm and QYs could also be obtained from the CdS QDs in a large-scale synthesis. The high-resolution transmission electron microscopy (HRTEM) images and powder X-ray diffraction (XRD) pattern suggested that the as-prepared QDs with high crystallinity had a cubic structure. A significant PL improvement and a continuous QY increase for the CdS QDs were observed during a long storage time in air and in a glovebox under room temperature. A slow surface reconstruction was proposed to be the cause for the PL enhancement of CdS QDs.
一种低成本、绿色且可重复的非注射式一锅法合成高质量的硫化镉量子点（CdS QDs）被报道。该合成在开放空气中进行，将前驱体硬脂酸镉和 S 粉混合到一种新溶剂 N-油酰吗啉中。观察到一个重叠的成核-生长阶段和一个主导生长阶段。所得的 QDs 表现出良好分辨的吸收精细结构和主导的带边发射，具有窄的尺寸分布（半峰全宽（fwhm）仅为 22-24nm）。最大光致发光（PL）量子产率（QY）高达 46.5%。从大规模合成的 CdS QDs 中也可以得到具有可调尺寸、相似 PL fwhm 和 QY 的高度单分散性 CdS QDs。高分辨率透射电子显微镜（HRTEM）图像和粉末 X 射线衍射（XRD）图谱表明，所制备的具有高结晶度的 QDs 具有立方结构。在空气和手套箱中在室温下长时间储存期间，观察到 CdS QDs 的 PL 显著改善和连续的 QY 增加。提出了一个缓慢的表面重构是导致 CdS QDs 的 PL 增强的原因。
