Morphological evolution in nanocrystalline CdS thin films from flowers to salt rock like structures
| Autor: | Tania Kalsi, Nupur Saxena, Pragati Kumar, Prateek Uttam |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
010302 applied physics
Materials science Photoluminescence Annealing (metallurgy) Band gap Organic Chemistry 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Atomic and Molecular Physics and Optics Nanocrystalline material Electronic Optical and Magnetic Materials Inorganic Chemistry symbols.namesake Chemical physics 0103 physical sciences symbols Electrical and Electronic Engineering Physical and Theoretical Chemistry Thin film 0210 nano-technology Raman spectroscopy Spectroscopy Chemical bath deposition Wurtzite crystal structure |
| Zdroj: | Optical Materials. 84:625-630 |
| ISSN: | 0925-3467 |
| DOI: | 10.1016/j.optmat.2018.07.068 |
| Popis: | Surface morphological evolution is observed in thermally activated nanocrystalline CdS (nc-CdS) thin films. The chemical bath deposited nc-CdS thin films show flower like structures on micro-crack background. Thermal annealing of nc-CdS thin films at different temperatures viz. 300, 350, 400 and 450 °C for 3 h in Ar ambient developed surface morphology towards salt rock like structures with clear particle boundaries at higher temperatures. Besides, structural phase transition from zincblende to wurtzite is observed, at 350 °C in nc-CdS thin films. It is observed that on increasing the annealing temperature longitudinal optical phonon Raman mode shifts toward higher frequency side in either of the crystal structure and bandgap reduces. Photoluminescence study illustrates thermally activated enhancement in green emission and disappearance of yellow and red emission in both the structures. The variation in emission intensity is described on the bases of morphology and structural changes occur due to thermal activation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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