Near band edge and defect emissions in wurtzite Cd0.025Mg0.10Zn0.875O nanocrystals
| Autor: | Andrés Cantarero, Carlos Rodríguez-Fernández, Maria R. Correia, Gabriel Rojas, A. Reyes-Rojas, Onyekachi Kalu, José Alberto Duarte Moller, J. Cardoso |
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| Rok vydání: | 2021 |
| Předmět: |
Materials science
Photoluminescence Band gap Organic Chemistry Analytical chemistry 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Atomic and Molecular Physics and Optics 0104 chemical sciences Electronic Optical and Magnetic Materials Inorganic Chemistry Crystallite Electrical and Electronic Engineering Physical and Theoretical Chemistry 0210 nano-technology Valence electron Spectroscopy Electronic band structure High-resolution transmission electron microscopy Wurtzite crystal structure |
| Zdroj: | Optical Materials. 118:111227 |
| ISSN: | 0925-3467 |
| DOI: | 10.1016/j.optmat.2021.111227 |
| Popis: | We report on near band edge and local defects emissions in Cd0·025Mg0·10Zn0·875O (CdMgZnO) nanoparticles (NPs) as a function of temperature, where a strong temperature-dependent near-infrared emission around 1.7 eV (~730 nm) has been observed. The NPs were synthesized by a modified sol-gel method and were annealed at 750 °C after growing. The crystallographic parameters have been determined by 2-dimensional synchrotron x-ray diffraction (XRD) and conventional XRD analysis, confirming their growth within the wurtzite phase with a preferred orientation along the (101) plane and an apparent crystallite size of 52.72 ± 0.18 nm. This apparent crystallite size is consistent with the nearly hexagonal particle shape (50.15 ± 0.38 nm) obtained from high resolution transmission electron microscopy. Valence Electron Energy Loss Spectroscopy (VEELS) has been conducted to gain information on the band structure and interband transitions. From the VEELS spectrum, an onset bandgap of 3.2 ± 0.3 eV was attributed to Cd/Mg co-doped ZnO. The temperature-dependent photoluminescence properties and enhancement of the optically active local defects emission have been analyzed. |
| Databáze: | OpenAIRE |
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