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浏览/检索结果: 共2条，第1-2条 帮助 限定条件 内容类型：会议论文     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 Optical characterization of bare CdSe and CdSe/CdS core/shell nanocrystals (EI CONFERENCE) 会议论文 ICO20: Biomedical Optics, August 21, 2005 - August 26, 2005, Changchun, China An L. M.; Sun P. N.; Liu L.; Feng X.; Kong L. P.; Bi H. N.; Yu B.; Kong X. G.; Liu Y. C. 收藏  |  浏览/下载：7/0  |  提交时间：2013/03/25 Thiol-capped CdSe/CdS core/shell nanocrystals (NCs) which show high luminescence quantum yield are synthesized in an aqueous solution. UV-Vis absorption spectroscopy and photoluminescence (PL) spectroscopy are employed to analyze optical characters and stabilities of NCs. Furthermore  PL properties are studied in a temperature range between 77K and 300K. The PL peak position of bare CdSe NCs shifts toward shorter wavelengths and the band becomes sharper with decreasing temperature. On the same condition  the PL peak position of CdSe/CdS core/shell NCs keeps unconverted nearly with the variation of temperature. Photostability of bare CdSe NCs and CdSe/CdS core/shell NCs are compared under the 325nm laser irradiation. It takes 78 seconds that the PL intensity declines to the half for CdSe NCs  but 442 seconds for CdSe/CdS core/shell NCs. The fluorescence decay lifetime increases about six times after overcoating. The results indicate that the CdS shell can improve the low temperature PL stability and photostability of CdSe NCs effectively.   Characterization of CdSe and CdSe/CdS core/shell nanoclusters synthesized in aqueous solution 会议论文 50th iumrs international conference on advanced materials, beijing, peoples r china, jun 13-18, 1999 作者:  Liu SM 收藏  |  浏览/下载：9/0  |  提交时间：2010/11/15 CdSe  CdSe/CdS  nanoclusters  QUANTUM DOTS  SEMICONDUCTOR NANOCRYSTALLITES  SIZE  EXCITON  CLUSTERS  DARK