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Effect on Electron Structure and Magneto-Optic Property of Heavy W-Doped Anatase TiO(2)

The spin or nonspin state of electrons in W-doped anatase TiO(2) is very difficult to judge experimentally because of characterization method limitations. Hence, the effect on the microscopic mechanism underlying the visible-light effect of W-doped anatase TiO(2) through the consideration of electro...

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Detalles Bibliográficos
Autores principales: Hou, Qingyu, Zhao, Chunwang, Guo, Shaoqiang, Mao, Fei, Zhang, Yue
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4425667/
https://www.ncbi.nlm.nih.gov/pubmed/25955308
http://dx.doi.org/10.1371/journal.pone.0122620
Descripción
Sumario:The spin or nonspin state of electrons in W-doped anatase TiO(2) is very difficult to judge experimentally because of characterization method limitations. Hence, the effect on the microscopic mechanism underlying the visible-light effect of W-doped anatase TiO(2) through the consideration of electronic spin or no-spin states is still unknown. To solve this problem, we establish supercell models of W-doped anatase TiO(2) at different concentrations, followed by geometry optimization and energy calculation based on the first-principle planewave norm conserving pseudo-potential method of the density functional theory. Calculation results showed that under the condition of nonspin the doping concentration of W becomes heavier, the formation energy becomes greater, and doping becomes more difficult. Meanwhile, the total energy increases, the covalent weakens and ionic bonds strengthens, the stability of the W-doped anatase TiO(2) decreases, the band gap increases, and the blue-shift becomes more significant with the increase of W doping concentration. However, under the condition of spin, after the band gap correction by the GGA+U method, it is found that the semimetal diluted magnetic semiconductors can be formed by heavy W-doped anatase TiO(2). Especially, a conduction electron polarizability of as high as near 100% has been found for the first time in high concentration W-doped anatase TiO(2). It will be able to be a promising new type of dilute magnetic semiconductor. And the heavy W-doped anatase TiO(2) make the band gap becomes narrower and absorption spectrum red-shift.