Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5402856 | Journal of Luminescence | 2010 | 6 Pages |
Abstract
CdSe quantum dots (QDs) prepared using an aqueous sodium selenosulphite and N,Nâ²-dimethylformamide (DMF) in commercial polymethylmethacrylate (PMMA) showed excellent optical properties. Tuning of the absorption and emission wavelengths by varying the selenium concentration with respect to cadmium is studied. As-prepared CdSe quantum dots showed absorption band at 405Â nm (3.06Â eV) associated with the formation of 'early-stage' CdSe nano-particles along with weak absorption at 480-90Â nm due to continuous growth of the particles. The blue-green and yellow-green light emissions were observed from as-prepared solutions. Photoluminescence (PL) measurement showed band-edge emissions at around 430Â nm for small clusters but a more stable emission at 544Â nm for the 1:1 CdSe sample. X-ray diffraction (XRD) pattern of the CdSe/PMMA powder with Cd/Se ratio of 1:1 showed broad pattern for cubic CdSe. Transmission electron microscopy (TEM) showed cube like de-shaped spherical dots in the region of about 5Â nm.
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Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
P.K. Khanna, Priyesh More, B.G. Bharate, A.K. Vishwanath,