First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub>
This study employs density functional theory (DFT) to investigate the electronic and optical properties of molybdenum (Mo) and chalcogen (S, Se, Te) co-doped anatase TiO<sub>2</sub>. Two co-doping configurations were examined: Model 1, where the dopants are adjacent, and Model 2, where t...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-07-01
|
| Series: | Computation |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2079-3197/13/7/170 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849246506924638208 |
|---|---|
| author | W. A. Chapa Pamodani Wanniarachchi Ponniah Vajeeston Talal Rahman Dhayalan Velauthapillai |
| author_facet | W. A. Chapa Pamodani Wanniarachchi Ponniah Vajeeston Talal Rahman Dhayalan Velauthapillai |
| author_sort | W. A. Chapa Pamodani Wanniarachchi |
| collection | DOAJ |
| description | This study employs density functional theory (DFT) to investigate the electronic and optical properties of molybdenum (Mo) and chalcogen (S, Se, Te) co-doped anatase TiO<sub>2</sub>. Two co-doping configurations were examined: Model 1, where the dopants are adjacent, and Model 2, where the dopants are farther apart. The incorporation of Mo into anatase TiO<sub>2</sub> resulted in a significant bandgap reduction, lowering it from 3.22 eV (pure TiO<sub>2</sub>) to range of 2.52–0.68 eV, depending on the specific doping model. The introduction of Mo-4d states below the conduction band led to a shift in the Fermi level from the top of the valence band to the bottom of the conduction band, confirming the n-type doping characteristics of Mo in TiO<sub>2</sub>. Chalcogen doping introduced isolated electronic states from Te-5<i>p</i>, S-3<i>p</i>, and Se-4<i>p</i> located above the valence band maximum, further reducing the bandgap. Among the examined configurations, Mo–S co-doping in Model 1 exhibited most optimal structural stability structure with the fewer impurity states, enhancing photocatalytic efficiency by reducing charge recombination. With the exception of Mo–Te co-doping, all co-doped systems demonstrated strong oxidation power under visible light, making Mo-S and Mo-Se co-doped TiO<sub>2</sub> promising candidates for oxidation-driven photocatalysis. However, their limited reduction ability suggests they may be less suitable for water-splitting applications. The study also revealed that dopant positioning significantly influences charge transfer and optoelectronic properties. Model 1 favored localized electron density and weaker magnetization, while Model 2 exhibited delocalized charge density and stronger magnetization. These findings underscore the critical role of dopant arrangement in optimizing TiO<sub>2</sub>-based photocatalysts for solar energy applications. |
| format | Article |
| id | doaj-art-b42e21772d1f401ba810907cd80112cf |
| institution | Kabale University |
| issn | 2079-3197 |
| language | English |
| publishDate | 2025-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Computation |
| spelling | doaj-art-b42e21772d1f401ba810907cd80112cf2025-08-20T03:58:27ZengMDPI AGComputation2079-31972025-07-0113717010.3390/computation13070170First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub>W. A. Chapa Pamodani Wanniarachchi0Ponniah Vajeeston1Talal Rahman2Dhayalan Velauthapillai3Faculty of Engineering, Western Norway University of Applied Sciences, 5020 Bergen, NorwayDepartment of Chemistry, Center for Materials Science and Nanotechnology, University of Oslo, P.O. Box 1033, Blindern, NO-0315 Oslo, NorwayFaculty of Engineering, Western Norway University of Applied Sciences, 5020 Bergen, NorwayFaculty of Engineering, Western Norway University of Applied Sciences, 5020 Bergen, NorwayThis study employs density functional theory (DFT) to investigate the electronic and optical properties of molybdenum (Mo) and chalcogen (S, Se, Te) co-doped anatase TiO<sub>2</sub>. Two co-doping configurations were examined: Model 1, where the dopants are adjacent, and Model 2, where the dopants are farther apart. The incorporation of Mo into anatase TiO<sub>2</sub> resulted in a significant bandgap reduction, lowering it from 3.22 eV (pure TiO<sub>2</sub>) to range of 2.52–0.68 eV, depending on the specific doping model. The introduction of Mo-4d states below the conduction band led to a shift in the Fermi level from the top of the valence band to the bottom of the conduction band, confirming the n-type doping characteristics of Mo in TiO<sub>2</sub>. Chalcogen doping introduced isolated electronic states from Te-5<i>p</i>, S-3<i>p</i>, and Se-4<i>p</i> located above the valence band maximum, further reducing the bandgap. Among the examined configurations, Mo–S co-doping in Model 1 exhibited most optimal structural stability structure with the fewer impurity states, enhancing photocatalytic efficiency by reducing charge recombination. With the exception of Mo–Te co-doping, all co-doped systems demonstrated strong oxidation power under visible light, making Mo-S and Mo-Se co-doped TiO<sub>2</sub> promising candidates for oxidation-driven photocatalysis. However, their limited reduction ability suggests they may be less suitable for water-splitting applications. The study also revealed that dopant positioning significantly influences charge transfer and optoelectronic properties. Model 1 favored localized electron density and weaker magnetization, while Model 2 exhibited delocalized charge density and stronger magnetization. These findings underscore the critical role of dopant arrangement in optimizing TiO<sub>2</sub>-based photocatalysts for solar energy applications.https://www.mdpi.com/2079-3197/13/7/170DFTco-dopedbandgapphotocatalysis |
| spellingShingle | W. A. Chapa Pamodani Wanniarachchi Ponniah Vajeeston Talal Rahman Dhayalan Velauthapillai First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub> Computation DFT co-doped bandgap photocatalysis |
| title | First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub> |
| title_full | First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub> |
| title_fullStr | First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub> |
| title_full_unstemmed | First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub> |
| title_short | First-Principles Insights into Mo and Chalcogen Dopant Positions in Anatase, TiO<sub>2</sub> |
| title_sort | first principles insights into mo and chalcogen dopant positions in anatase tio sub 2 sub |
| topic | DFT co-doped bandgap photocatalysis |
| url | https://www.mdpi.com/2079-3197/13/7/170 |
| work_keys_str_mv | AT wachapapamodaniwanniarachchi firstprinciplesinsightsintomoandchalcogendopantpositionsinanatasetiosub2sub AT ponniahvajeeston firstprinciplesinsightsintomoandchalcogendopantpositionsinanatasetiosub2sub AT talalrahman firstprinciplesinsightsintomoandchalcogendopantpositionsinanatasetiosub2sub AT dhayalanvelauthapillai firstprinciplesinsightsintomoandchalcogendopantpositionsinanatasetiosub2sub |