Yang Heesun, Holloway Paul H, Cunningham Garry, Schanze Kirk S
Department of Materials Science and Engineering, University of Florida, Gainesville, Florida 32611, USA.
J Chem Phys. 2004 Nov 22;121(20):10233-40. doi: 10.1063/1.1808418.
Synthesis and characterization of highly luminescent ZnS-passivated CdS:Mn (CdS:Mn/ZnS) core/shell structured nanocrystals are reported. Mn-doped CdS core nanocrystals are produced ranging from 1.5 to 2.3 nm in diameter with epitaxial ZnS shell of wider band gap via a reverse micelle process. UV irradiation-stimulated photo-oxidation of the ZnS shell results in formation of sulfate (ZnSO(4)) as determined by x-ray photoelectron spectroscopy, which increases the photoluminescence emission intensity and subsequent photostability. Luminescent relaxation lifetime data present two different decay components, consisting of slow decay emission from the Mn center and a fast decay emission from a defect-related center. The impact of the density of surface defect states upon the emission spectra is discussed.
锰（CdS:Mn/ZnS）核壳结构纳米晶体的合成与表征。通过反胶束法制备了直径在1.5至2.3纳米之间的锰掺杂硫化镉核纳米晶体，并在外层包覆了具有较宽带隙的外延硫化锌壳层。X射线光电子能谱测定结果表明，紫外光照射引发的硫化锌壳层光氧化作用导致形成了硫酸锌（ZnSO₄），这提高了光致发光发射强度以及后续的光稳定性。发光弛豫寿命数据呈现出两个不同的衰减成分，包括来自锰中心的缓慢衰减发射和来自缺陷相关中心的快速衰减发射。讨论了表面缺陷态密度对发射光谱的影响。
