ORALS
SESSION: ManufacturingWedPM2-R4
Environmental Aspects / Impact on Climate Change | Mamalis International Symposium on Advanced Manufacturing of Advanced Materials and Structures with Sustainable Industrial Applications |
| Wed Nov, 7 2018 / Room: Sao Conrado (50/2nd) | |
| Session Chairs: Sesh Commuri; Session Monitor: TBA |
16:20: [ManufacturingWedPM210]
DFT Insights into the Role of Relative Positions of Fe and N Dopants on the Structure and Properties of TiO2 Sahar Ramin
Gul
1 ;
Matiullah
Khan2 ; Zeng
Yi
3 ; Bo
Wu
1 ;
Athanasios G.
Mamalis4 ;
1Multiscale Computational Materials Facility, College of Materials Science and Engineering, Fuzhou University, Fuzhou, China;
2Kohat University of Science and Technology, Kohat, Pakistan;
3State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China;
4PC-NAE, Demokritos National Center for Scientific Research, Athens, Greece;
Paper Id: 32
[Abstract] The location and nature of doped elements strongly affect the structural, electronic, and optical properties of TiO<sub>2</sub>. To tailor the band structure and modify the photoelectrochemical properties of TiO<sub>2</sub>, a pair of dopants is selected. Fe and N atoms are inserted in the TiO<sub>2</sub> network at substitutional and interstitial sites with different relative distances. The main objective behind the different locations and sites of the doped elements is to banish the isolated unoccupied states from the forbidden region that normally annihilates the photogenerated carriers. Fe at the Ti site and N at the O site doped in the TiO<sub>2</sub> network separated at a distance of 7.805 Å provided a suitable configuration of dopant atoms in terms of geometry and band structure. Moreover, the optical properties showed a notable shift to the visible regime. Individual dopants either introduced isolated unoccupied states in the band gap or disturbed the fermi level and structural properties. Furthermore, the other co-doped configurations showed no remarkable band shift, as well as exhibiting a suitable band structure. Resultantly, comparing the band structure and optical properties, it is argued that Fe (at Ti) and N (at O) doped at a distance of 7.805 Å would strongly improve the photoelectrochemical properties of TiO<sub>2</sub>.
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