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Published on: October 9, 2012
Energy level splitting of CdS nanocrystals
1State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan, People's Republic of China. gltan@whut.edu.cn
Abstract:
CdS nanocrystals have been fabricated using mercaptopropionic acid (MPA) as the stabilizing agent and Na(2)S as a sulfur source. The structure and morphology of the CdS nanocrystals have been measured by x-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM). Energy level splitting was observed in the UV-VIS optical absorption spectrum of small CdS nanocrystals; the main absorption peak splits into three separate peaks, which are considered to be three discrete sub-energy levels of the 1S electronic state of the CdS nanocrystals.
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