Effect of Co2+ doping on Raman spectra and the phase transformation of TiO2:Co2+ nanowires
| Autor: | Trinh Thi Loan, Nguyen Ngoc Long |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Anatase
Photoluminescence Materials science Absorption spectroscopy Band gap Nanowire Physics::Optics 02 engineering and technology 010402 general chemistry 01 natural sciences Condensed Matter::Materials Science symbols.namesake Physics::Atomic and Molecular Clusters General Materials Science Physics::Atmospheric and Oceanic Physics Doping General Chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 0104 chemical sciences Crystallography symbols Astrophysics::Earth and Planetary Astrophysics 0210 nano-technology Raman spectroscopy Raman scattering |
| Zdroj: | Journal of Physics and Chemistry of Solids. 124:336-342 |
| ISSN: | 0022-3697 |
| DOI: | 10.1016/j.jpcs.2018.09.007 |
| Popis: | Co2+-doped anatase TiO2 nanowires were successfully synthesized by hydrothermal method. Inhibitory effect of Co2+-doping on the anatase to rutile phase transformation was investigated by X-ray diffraction, Raman scattering. The replacement of Ti4+ ions with Co2+ ions led to a slight expansion of the unit cell volume and a shift and broadening of all the characteristic Raman scattering modes of the anatase TiO2:Co2+ nanowires. The absorption spectra exhibited the band-band transitions of TiO2 host and the transitions within Co2+ ions located in octahedral field of the anatase TiO2 nanowires. Co2+-doping reduced both the indirect and the direct band gaps. Photoluminescence spectra of the undoped anatase TiO2:Co2+ nanowires showed the transitions between the bands and the transitions related to surface defect states, oxygen vacancies. The Co2+-doping caused only the quenching phenomenon of emission of the TiO2 nanowires. |
| Databáze: | OpenAIRE |
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