Opoku, FGovender, KrishnaVan Sittert, CGCEGovender, PP2017-11-212017-11-212017-09Opoku, F. et al. 2017. Understanding the synergistic effects, optical and electronic properties of ternary Fe/C/S-doped TiO2 anatase within the DFT 1 U approach. International Journal of Quantum Chemistry, e25505, DOI: 10.1002/qua.255050020-7608http://onlinelibrary.wiley.com/doi/10.1002/qua.25505/fullDOI: 10.1002/qua.25505http://hdl.handle.net/10204/9807Copyright: 2017 Wiley. Due to copyright restrictions, the attached PDF file only contains the abstract of the full text item. For access to the full text item, please consult the publisher's website.Although TiO2 is an efficient photocatalyst, its large band gap limits its photocatalytic activity only to the ultraviolet region. An experimentally synthesized ternary Fe/C/S-doped TiO2 anatase showed improved visible light photocatalytic activity. However, a theoretical study of the underlying mechanism of the enhanced photocatalytic activity and the interaction of ternary Fe/C/S-doped TiO2 has not yet been investigated. In this study, the defect formation energy, electronic structure and optical property of TiO2doped with Fe, C, and S are investigated in detail using the density functional theory + U method. The calculated band gap (3.21 eV) of TiO2anatase agree well with the experimental band gap (3.20 eV). The defect formation energy shows that the co- and ternary-doped systems are thermodynamically favorable under oxygen-rich condition. Compared to the undoped TiO2, the absorption edge of the mono-, co-, and ternary-doped TiO2 is significantly enhanced in the visible light region. We have shown that ternary doping with C, S, and Fe induces a clean band structure without any impurity states. Moreover, the ternary Fe/C/S-doped TiO2 exhibit an enhanced photocatalytic activity, a smaller band gap and negative formation energy compared to the mono- and co-doped systems. Moreover, the band edges of Fe/C/S-doped TiO2 align well with the redox potentials of water, which shows that the ternary Fe/C/S-doped TiO2 is promising photocatalysts to split water into hydrogen and oxygen. These findings rationalize the available experimental results and can assist the design of TiO2-based photocatalyst materials.enDFT 1 U methodFormation energyPhotocatalysisTiO2 anataseWater splittingArticleOpoku, F., Govender, K., Van Sittert, C., & Govender, P. (2017). Understanding the synergistic effects, optical and electronic properties of ternary Fe/C/S-doped TiO2 anatase within the DFT 1 U approach. http://hdl.handle.net/10204/9807Opoku, F, Krishna Govender, CGCE Van Sittert, and PP Govender "Understanding the synergistic effects, optical and electronic properties of ternary Fe/C/S-doped TiO2 anatase within the DFT 1 U approach." (2017) http://hdl.handle.net/10204/9807Opoku F, Govender K, Van Sittert C, Govender P. Understanding the synergistic effects, optical and electronic properties of ternary Fe/C/S-doped TiO2 anatase within the DFT 1 U approach. 2017; http://hdl.handle.net/10204/9807.TY - Article AU - Opoku, F AU - Govender, Krishna AU - Van Sittert, CGCE AU - Govender, PP AB - Although TiO2 is an efficient photocatalyst, its large band gap limits its photocatalytic activity only to the ultraviolet region. An experimentally synthesized ternary Fe/C/S-doped TiO2 anatase showed improved visible light photocatalytic activity. However, a theoretical study of the underlying mechanism of the enhanced photocatalytic activity and the interaction of ternary Fe/C/S-doped TiO2 has not yet been investigated. In this study, the defect formation energy, electronic structure and optical property of TiO2doped with Fe, C, and S are investigated in detail using the density functional theory + U method. The calculated band gap (3.21 eV) of TiO2anatase agree well with the experimental band gap (3.20 eV). The defect formation energy shows that the co- and ternary-doped systems are thermodynamically favorable under oxygen-rich condition. Compared to the undoped TiO2, the absorption edge of the mono-, co-, and ternary-doped TiO2 is significantly enhanced in the visible light region. We have shown that ternary doping with C, S, and Fe induces a clean band structure without any impurity states. Moreover, the ternary Fe/C/S-doped TiO2 exhibit an enhanced photocatalytic activity, a smaller band gap and negative formation energy compared to the mono- and co-doped systems. Moreover, the band edges of Fe/C/S-doped TiO2 align well with the redox potentials of water, which shows that the ternary Fe/C/S-doped TiO2 is promising photocatalysts to split water into hydrogen and oxygen. These findings rationalize the available experimental results and can assist the design of TiO2-based photocatalyst materials. DA - 2017-09 DB - ResearchSpace DP - CSIR KW - DFT 1 U method KW - Formation energy KW - Photocatalysis KW - TiO2 anatase KW - Water splitting LK - https://researchspace.csir.co.za PY - 2017 SM - 0020-7608 T1 - Understanding the synergistic effects, optical and electronic properties of ternary Fe/C/S-doped TiO2 anatase within the DFT 1 U approach TI - Understanding the synergistic effects, optical and electronic properties of ternary Fe/C/S-doped TiO2 anatase within the DFT 1 U approach UR - http://hdl.handle.net/10204/9807 ER -