Photophysical Properties of CdSe/CdS core/shell quantum dots with tunable surface composition
作者： Kelly L. Sowers , Zhentao Hou , Jeffrey J. Peterson , Brett Swartz , Sougata Pal
DOI: 10.1016/J.CHEMPHYS.2015.09.010
关键词:
摘要: Abstract We report the synthesis and optical characterization of core/shell CdSe/CdS quantum dots (QDs) with controlled surface composition. Using secondary phosphine chalcogenide cadmium carboxylate precursors in an alternating layer-by-layer synthetic approach, elemental composition quasi-type-I QDs can be repeatedly tuned from predominately to predominantly sulfur, as measured by X-ray photoelectron spectroscopy (XPS). Similar CdS CdSe core-only QDs, has a significant effect on photoluminescence (PL) yield: sulfur terminated exhibit quenched PL, while have relatively bright PL. Density-functional tight-binding calculations clusters suggest that PL quenching for sulfur-rich surfaces is result high density hole states QD bandgap. Time-resolved measurements confirm QDs’ nonradiative recombination rates are strongly sensitive
elsevier.com
sci-hub.se 参考文章(71)
Anthony R. West, Basic Solid State Chemistry ,(1988)
N. J. Borys, M. J. Walter, J. Huang, D. V. Talapin, J. M. Lupton, The role of particle morphology in interfacial energy transfer in CdSe/CdS heterostructure nanocrystals Science. ,vol. 330, pp. 1371- 1374 ,(2010) , 10.1126/SCIENCE.1198070
Jacek Jasieniak, Paul Mulvaney, From Cd-rich to se-rich--the manipulation of CdSe nanocrystal surface stoichiometry. Journal of the American Chemical Society. ,vol. 129, pp. 2841- 2848 ,(2007) , 10.1021/JA066205A
Xinhua Zhong, Mingyong Han, Zhili Dong, Timothy J White, Wolfgang Knoll, None, Composition-tunable ZnxCd1-xSe nanocrystals with high luminescence and stability Journal of the American Chemical Society. ,vol. 125, pp. 8589- 8594 ,(2003) , 10.1021/JA035096M
Christopher M. Evans, Li Guo, Jeffrey J. Peterson, Sara Maccagnano-Zacher, Todd D. Krauss, Ultrabright PbSe magic-sized clusters. Nano Letters. ,vol. 8, pp. 2896- 2899 ,(2008) , 10.1021/NL801685A
Bradley F. Habenicht, Colleen F. Craig, Oleg V. Prezhdo, Time-Domain Ab Initio Simulation of Electron and Hole Relaxation Dynamics in a Single-Wall Semiconducting Carbon Nanotube Physical Review Letters. ,vol. 96, pp. 187401- ,(2006) , 10.1103/PHYSREVLETT.96.187401
Haiming Zhu, Tianquan Lian, Wavefunction engineering in quantum confined semiconductor nanoheterostructures for efficient charge separation and solar energy conversion Energy and Environmental Science. ,vol. 5, pp. 9406- 9418 ,(2012) , 10.1039/C2EE22679K
Nicholas C. Anderson, Mark P. Hendricks, Joshua J. Choi, Jonathan S. Owen, Ligand exchange and the stoichiometry of metal chalcogenide nanocrystals: spectroscopic observation of facile metal-carboxylate displacement and binding. Journal of the American Chemical Society. ,vol. 135, pp. 18536- 18548 ,(2013) , 10.1021/JA4086758
R. Rossetti, S. Nakahara, L. E. Brus, Quantum size effects in the redox potentials, resonance Raman spectra, and electronic spectra of CdS crystallites in aqueous solution The Journal of Chemical Physics. ,vol. 79, pp. 1086- 1088 ,(1983) , 10.1063/1.445834
Matthew T. Frederick, Emily A. Weiss, Relaxation of exciton confinement in CdSe quantum dots by modification with a conjugated dithiocarbamate ligand. ACS Nano. ,vol. 4, pp. 3195- 3200 ,(2010) , 10.1021/NN1007435