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Inorganic Surface Passivation of PbS Nanocrystals resulting in Strong Photoluminescent Emission

M. J. Fernee·A. Watt·J. Warner·S. Cooper·N. Heckenberg·H. Rubinsztein-Dunlop
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Abstract

Strong photoluminescent emission has been obtained from 3 nm PbS nanocrystals in aqueous colloidal solution, following treatment with CdS precursors. The observed emission can extend across the entire visible spectrum and usually includes a peak near 1.95 eV. We show that much of the visible emission results from absorption by higher-lying excited states above 3.0 eV with subsequent relaxation to and emission from states lying above the observed band-edge of the PbS nanocrystals. The fluorescent lifetimes for this emission are in the nanosecond regime, characteristic of exciton recombination.

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M. J. Fernee, A. Watt, J. Warner, S. Cooper, N. Heckenberg, H. Rubinsztein-Dunlop. 2003-03-14. Inorganic Surface Passivation of PbS Nanocrystals resulting in Strong Photoluminescent Emission. https://doi.org/10.1088/0957-4484%2F14%2F9%2F311

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