Enhancement of photoluminescence in ZnS/ZnO quantum dots interfacial heterostructures
| Autor: | S. Sohila, M. Rajalakshmi, G. M. Bhalerao, Ramamoorthy Ramesh |
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| Rok vydání: | 2012 |
| Předmět: |
Photoluminescence
Materials science Absorption spectroscopy Condensed matter physics Condensed Matter::Other Phonon Mechanical Engineering Physics::Optics Heterojunction Condensed Matter::Mesoscopic Systems and Quantum Hall Effect Condensed Matter Physics Blueshift Condensed Matter::Materials Science symbols.namesake Mechanics of Materials Quantum dot symbols General Materials Science Raman spectroscopy Wurtzite crystal structure |
| Zdroj: | Materials Research Bulletin. 47:2668-2672 |
| ISSN: | 0025-5408 |
| DOI: | 10.1016/j.materresbull.2012.03.006 |
| Popis: | ZnS/ZnO quantum dots (QDs) were synthesized by controlled oxidation of ZnS nanoparticles. HRTEM image showed small nanocrystals of size 4 nm and the magnified image of single quantum dot shows interfacial heterostructure formation. The optical absorption spectrum shows a blue shift of 0.19 and 0.23 eV for ZnO and ZnS QDs, respectively. This is due to the confinement of charge carries within the nanostructures. Enormous enhancement in UV emission (10 times) is reported which is attributed to interfacial heterostructure formation. Raman spectrum shows phonons of wurtzite ZnS and ZnO. Phonon confinement effect is seen in the Raman spectrum wherein LO phonon peaks of ZnS and ZnO are shifted towards lower wavenumber side and are broadened. |
| Databáze: | OpenAIRE |
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