tailieunhanh - Báo cáo hóa học: " Facile Synthesis of Monodisperse CdS Nanocrystals via Microreaction"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Facile Synthesis of Monodisperse CdS Nanocrystals via Microreaction | Nanoscale Res Lett 2010 5 130-137 DOI s11671-009-9454-z NANO EXPRESS Facile Synthesis of Monodisperse CdS Nanocrystals via Microreaction Zhen Wan Hongwei Yang Weiling Luan Shan-tung Tu Xinggui Zhou Received 2 July 2009 Accepted 25 September 2009 Published online 13 October 2009 to the authors 2009 Abstract CdS-based nanocrystals NCs have attracted extensive interest due to their potential application as key luminescent materials for blue and white LEDs. In this research the continuous synthesis of monodisperse CdS NCs was demonstrated utilizing a capillary microreactor. The enhanced heat and mass transfer in the microreactor was useful to reduce the reaction temperature and residence time to synthesize monodisperse CdS NCs. The superior stability of the microreactor and its continuous operation allowed the investigation of synthesis parameters with high efficiency. Reaction temperature was found to be a key parameter for balancing the reactivity of CdS precursors while residence time was shown to be an important factor that governs the size and size distribution of the CdS NCs. Furthermore variation of OA concentration was demonstrated to be a facile tuning mechanism for controlling the size of the CdS NCs. The variation of the volume percentage of OA from to and the variation of the residence time from 17 to 136 s facilitated the synthesis of monodisperse CdS NCs in the size range of nm and the NCs produced photoluminescent emissions in the range of 391-463 nm. Keywords Microreaction Quantum dots CdS Nanocrystals Z. Wan H. Yang W. Luan H S. Tu State Key Laboratory of Safety Science of Pressurized System School of Mechanical and Power Engineering East China University of Science and Technology 200237 Shanghai China e-mail luan@ X. Zhou State Key Laboratory of Chemical Engineering East China University of Science and Technology 200237 Shanghai China Introduction The strong quantum confinement effect of colloidal semiconductor .