Effect of Oxygen Admittance Temperature on the Growth of ZnO Microcrystals by Thermal Evaporation Technique
| Autor: | K.M.K. Srivatsa, Deepak Chhikara, M. Senthil Kumar |
|---|---|
| Rok vydání: | 2012 |
| Předmět: |
Photoluminescence
Materials science Admittance Polymers and Plastics Atmospheric pressure Scanning electron microscope Mechanical Engineering Metals and Alloys Analytical chemistry chemistry.chemical_element medicine.disease_cause Oxygen Spectral line chemistry Mechanics of Materials Transmission electron microscopy Materials Chemistry Ceramics and Composites medicine Ultraviolet |
| Zdroj: | Journal of Materials Science & Technology. 28:317-320 |
| ISSN: | 1005-0302 |
| DOI: | 10.1016/s1005-0302(12)60061-9 |
| Popis: | Hexagonally well-faceted microcrystals of ZnO have been grown by thermal evaporation of Zn powder in oxygen ambient at 700 °C under atmospheric pressure. It has been observed that the properties (size and quality) of ZnO microcrystals have a strong dependence on the reactor temperature at which the oxygen gas is admitted into the growth zone. The microcrystals grown with oxygen admittance at 450 °C have a length of 1 μm and a diameter of 0.75 μm while that grown with oxygen admittance at 600 °C have a length of 1.5–2 μm and a diameter of 1 μm. Room temperature photoluminescence spectra show a ultraviolet (UV) emission peak at 385 nm with a green band emission at around 500 nm. The UV-to-green band emission ratio for the microcrystals grown with oxygen admittance at 450 °C is observed to be 1.25 and the ratio decreases to 0.45 for the sample grown with oxygen admittance at 600 °C. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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