tailieunhanh - Báo cáo hóa học: " CdSe Ring- and Tribulus-Shaped Nanocrystals: Controlled Synthesis, Growth Mechanism, and Photoluminescence Properties"

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: CdSe Ring- and Tribulus-Shaped Nanocrystals: Controlled Synthesis, Growth Mechanism, and Photoluminescence Properties | Nanoscale Res Lett 2009 4 437-443 DOI S11671-009-9265-2 NANO EXPRESS CdSe Ring- and Tribulus-Shaped Nanocrystals Controlled Synthesis Growth Mechanism and Photoluminescence Properties Pengfei Hu Dianzeng Jia Yali Cao Yudai Huang Lang Liu Jianmin Luo Received 24 November 2008 Accepted 27 January 2009 Published online 18 February 2009 to the authors 2009 Abstract With air-stable and generic reagents CdSe nanocrystals with tunable morphologies were prepared by controlling the temperature in the solution reaction route. Thereinto the lower reaction temperature facilitates the anisotropic growth of crystals to obtain high-yield CdSe ring- and tribulus-shaped nanocrystals with many branches on their surfaces. The photoluminescence properties are sensitive to the nature of particle and its surface. The products synthesized at room temperature whose surfaces have many branches show higher blue shift and narrower emission linewidths FWHM of photoluminescence than that of samples prepared at higher temperature whose surfaces have no branches. Microstructural studies revealed that the products formed through self-assembly of primary crystallites. Nanorings formed through the nonlinear attachment of primary crystallites and the branches on the surfaces grew by linear attachment at room temperature. And the structure of tribulus-shaped nanoparticle was realized via two steps of aggregation . random and linear oriented aggregation. Along with the elevation of temperature the branches on nanocrystal surfaces shortened gradually because of the weakened linear attachment. Electronic supplementary material The online version of this article doi s11671-009-9265-2 contains supplementary material which is available to authorized users. P. Hu D. Jia El Y. Cao Y. Huang L. Liu Institute of Applied Chemistry Xinjiang University Urumqi 830046 People s Republic of China e-mail jdz@ J. Luo Physics and Chemistry Test Centre Xinjiang University Urumqi 830046 People