Chou Pi-Tai, Chen Chun-Yen, Cheng Chiu-Ting, Pu Shih-Chieh, Wu Kun-Chan, Cheng Yi-Ming, Lai Chih-Wei, Chou Yi-Hsuan, Chiu Hsin-Tien
Department of Chemistry, National Taiwan University, Taipei 106, Taiwan.
Chemphyschem. 2006 Jan 16;7(1):222-8. doi: 10.1002/cphc.200500307.
Syntheses of CdTe/CdSe type-II quantum dots (QDs) using CdO and CdCl2 as precursors for core and shell, respectively, are reported. Characterization was made via near-IR interband emission, transmission electron microscopy (TEM), energy dispersive spectroscopy (EDX), and X-ray diffraction (XRD). Femtosecond fluorescence upconversion measurements on the relaxation dynamics of the CdTe core (in CdTe/CdSe) emission and CdTe/CdSe interband emission reveal that as the size of the core increases from 5.3, 6.1 to 6.9 nm, the rate of photoinduced electron separation decreases from 1.96, 1.44 to 1.07 x10(12) s(-1). The finite rates of the initial charge separation are tentatively rationalized by the small electron-phonon coupling, causing weak coupling between the initial and charge-separated states.
报道了分别使用氧化镉和氯化镉作为核和壳的前驱体合成CdTe/CdSe II型量子点（QDs）的方法。通过近红外带间发射、透射电子显微镜（TEM）、能量色散光谱（EDX）和X射线衍射（XRD）进行表征。对CdTe核（在CdTe/CdSe中）发射和CdTe/CdSe带间发射的弛豫动力学进行的飞秒荧光上转换测量表明，随着核尺寸从5.3、6.1增加到6.9 nm，光致电子分离速率从1.96、1.44降低到1.07×10¹² s⁻¹。初始电荷分离的有限速率初步归因于小的电子 - 声子耦合，导致初始态和电荷分离态之间的弱耦合。
