Water treatment Titania Photocatalysis Electrophotocatalysis Doping
Abstract :
[en] The objective of this study is to investigate the enhancement of TiO2 photocatalytic activity under UV/visible and visible light by doping with tantalum (Ta), vanadium (V) or niobium (Nb) precursors. Thus, TiO2-based photocatalysts are prepared at room temperature via aqueous sol-gel synthesis. These photocatalysts are doped with different molar ratios of dopants. The physicochemical properties of the obtained photocatalysts are characterized using various complementary techniques. X-ray diffraction (XRD) is used to determine the distribution of different crystalline phases of TiO2 and the proportion of amorphous TiO2 in the samples. BET measurements give textural properties with specific surface area reaching up to 292 m2/g and TEM images illustrating their spherical morphology. Inductively coupled plasma atomic emission spectroscopy (ICP-AES), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS) analyses confirmed the presence of Ti, O and Ta, V or Nb elements in the samples. Additionally, XPS spectra highlights the incorporation of nitrogen in the undoped synthesized TiO2. Additionally, band gap widths measured by UV-vis diffuse reflectance spectroscopy (DRUS) are done to see the impact of the dopants on the bandgap, with V-doping reducing its value from 2.95 to 1.88 eV. A screening of the photocatalytic activity of undoped and doped photocatalysts is carried out by evaluating the degradation of p-nitrophenol under UV-visible light (300 < λ < 800 nm) and visible light only (395 < λ < 800 nm). This study suggests that photocatalytic activity is significantly influenced by the nature and dopant content. Photocatalytic tests show an improvement in the activity of the photocatalyst when doped with tantalum and niobium (from 22 % with undoped TiO2 under visible light to 37 % and 55 % with the best Ta and Nb-doped samples respectively), while a notable decrease in activity is observed with vanadium doping (dropping to 3-12 % with the V-doped series). Finally, a preliminary electrophotocatalysis experimental setup is implemented and appears to show an improvement in the mineralization of the PNP solution when the anode is coated with layers of the best doped-TiO2 material (Nd doping), compared to an uncoated anode (the mineralization rate increases from 72 % to 94 %).
Disciplines :
Materials science & engineering Chemical engineering
Author, co-author :
Farcy, Antoine ; Université de Liège - ULiège > Chemical engineering
Lambert, Stéphanie ; Université de Liège - ULiège > Department of Chemical Engineering
Mathy, Maxine; Department of Chemical Engineering -Nanomaterials, Catalysis & Electrochemistry, University of Liège, Liège, Belgium
Lejeune, Louise; Institute of Condensed Matter and Nanosciences -Molecular Chemistry, Materials and Catalysis (IMCN/MOST), Université catholique de Louvain, Louvain-La-Neuve, Belgium
Eloy, Pierre; Institute of Condensed Matter and Nanosciences -Molecular Chemistry, Materials and Catalysis (IMCN/MOST), Université catholique de Louvain, Louvain-La-Neuve, Belgium
Hermans, Sophie; Institute of Condensed Matter and Nanosciences -Molecular Chemistry, Materials and Catalysis (IMCN/MOST), Université catholique de Louvain, Louvain-La-Neuve, Belgium
Mahy, Julien ; Université de Liège - ULiège > Chemical engineering
Language :
English
Title :
Optimization of Ta-, V-, or Nb-doped TiO2 for photocatalytic and electrophotocatalytic degradation of p-nitrophenol under UV-visible light
Publication date :
01 October 2025
Journal title :
Journal of Photochemistry and Photobiology A: Chemistry
A. Gupta, M.R. Singh, Water Pollution-Sources, Effects and Control (2016) 1–16. https://www.researchgate.net/publication/321289637.
Mahy, J.G., Lambert, S.D., Tilkin, R.G., Wolfs, C., Poelman, D., Devred, F., Gaigneaux, E.M., Douven, S., Ambient temperature ZrO2-doped TiO2 crystalline photocatalysts: highly efficient powders and films for water depollution. Mater. Today Energy, 13, 2019, 10.1016/j.mtener.2019.06.010.
Kumar Reddy, D.H., Lee, S.M., Water pollution and treatment technologies. J. Environ. Anal. Toxicol., 02, 2012, 10.4172/2161-0525.1000e103.
Adeleye, A.S., Xue, J., Zhao, Y., Taylor, A.A., Zenobio, J.E., Sun, Y., Han, Z., Salawu, O.A., Zhu, Y., Abundance, fate, and effects of pharmaceuticals and personal care products in aquatic environments. J. Hazard. Mater., 424, 2022, 10.1016/j.jhazmat.2021.127284.
Díaz-Gamboa, L., Martínez-López, S., Ayuso-García, L.M., Lahora, A., Martínez-Alcalá, I., Can lagoons serve as a quaternary treatment for micropollutants in wastewater treatment plants? Recent implications for compliance with the new urban wastewater treatment directive. Environments - MDPI, 11, 2024, 10.3390/environments11060105.
Bustillo-Lecompte, C., Colina-Marquez, J., Rehmann, L., Special issue: application of advanced oxidation processes. Processes, 8, 2020, 10.3390/PR8070867.
Deng, Y., Zhao, R., Advanced Oxidation Processes (AOPs) in wastewater treatment. Curr. Pollut. Rep. 1 (2015), 167–176, 10.1007/s40726-015-0015-z.
Fadhel, A.Z., Pollet, P., Liotta, C.L., Eckert, C.A., Combining the benefits of homogeneous and heterogeneous catalysis with tunable solvents and nearcritical water. Molecules 15 (2010), 8400–8424, 10.3390/molecules15118400.
Cao, D., Wang, Y., Zhao, X., Combination of photocatalytic and electrochemical degradation of organic pollutants from water. Curr. Opin. Green Sust. Chem. 6 (2017), 78–84, 10.1016/j.cogsc.2017.05.007.
Pelaez, M., Nolan, N.T., Pillai, S.C., Seery, M.K., Falaras, P., Kontos, A.G., Dunlop, P.S.M., Hamilton, J.W.J., Byrne, J.A., O'Shea, K., Entezari, M.H., Dionysiou, D.D., A review on the visible light active titanium dioxide photocatalysts for environmental applications. Appl. Catal. B 125 (2012), 331–349, 10.1016/j.apcatb.2012.05.036.
Farcy, A., Mathy, M., Lejeune, L., Eloy, P., Hermans, S., Drogui, P., Mahy, J.G., Ce2O3 and TiO2 p-n heterojunction for enhanced degradation of p-nitrophenol under visible light. J. Photochem. Photobiol. A Chem., 463, 2025, 10.1016/j.jphotochem.2025.116284.
Tee, S.Y., Kong, J., Koh, J.J., Teng, C.P., Wang, X.Z., Wang, X., Teo, S.L., Thitsartarn, W., Han, M.-Y., Seh, Z.W., Structurally and surficially activated TiO2 nanomaterials for photochemical reactions. Nanoscale, 16, 2024, 18165, 10.1039/d4nr02342k.
Bashir, N., Sawaira, T., Jamil, A., Awais, M., Habib, A., Afzal, A., Challenges and prospects of main-group metal-doped TiO2 photocatalysts for sustainable water remediation. Mater. Today Sust., 27, 2024, 10.1016/j.mtsust.2024.100869.
Geldasa, F.T., Dejene, F.B., Kebede, M.A., Hone, F.G., Jira, E.T., Density functional theory study of chlorine, fluorine, nitrogen, and sulfur doped rutile TiO2 for photocatalytic application. Sci. Rep., 15, 2025, 3390, 10.1038/s41598-024-84316-0.
Din, M.I., Khalid, R., Photocatalysis of pharmaceuticals and organic dyes in the presence of silver-doped TiO2 photocatalyst–A critical review. Int. J. Environ. Anal. Chem. 105 (2025), 276–300, 10.1080/03067319.2023.2258795.
Mahy, J.G., Paez, C.A., Carcel, C., Bied, C., Tatton, A.S., Damblon, C., Heinrichs, B., Wong Chi Man, M., Lambert, S.D., Porphyrin-based hybrid silica-titania as a visible-light photocatalyst. J. Photochem. Photobiol. A Chem., 373, 2019, 10.1016/j.jphotochem.2019.01.001.
Min, K.S., Kumar, R.S., Lee, J.H., Kim, K.S., Lee, S.G., Son, Y.A., Synthesis of new TiO2/porphyrin-based composites and photocatalytic studies on methylene blue degradation. Dyes Pigm. 160 (2019), 37–47, 10.1016/j.dyepig.2018.07.045.
Zhang, X., Duan, Q., Dong, W., Cui, X., Xing, G., Duan, Y., A novel asymmetric porphyrin-sensitized Fe2C/ TiO2 magnetic porous nanofiber composite photocatalyst for highly efficient degradation of bisphenol A by potassium peroxydisulfate activation. Sep. Purif. Technol., 363, 2025, 10.1016/j.seppur.2025.132300.
Páez, C.A., Poelman, D., Pirard, J.P., Heinrichs, B., Unpredictable photocatalytic ability of H2-reduced rutile- TiO2 xerogel in the degradation of dye-pollutants under UV and visible light irradiation. Appl. Catal. B 94 (2010), 263–271, 10.1016/j.apcatb.2009.11.017.
Simeonov, S., Szekeres, A., Covei, M., Stroescu, H., Nicolescu, M., Chesler, P., Hornoiu, C., Gartner, M., Sol-gel multilayered niobium (vanadium)-doped TiO2 for CO sensing and photocatalytic degradation of methylene blue. Materials, 17, 2024, 10.3390/ma17081923.
de la Cruz-de los Santos, J.E., García-Zaleta, D.S., Encarnación-Gómez, C., Martínez-Corona, Z., López-González, R., Álvarez-Lemus, M.A., Morales-Bautista, C.M., Palma-Ramírez, D., Reyes-Montero, A., Photocatalytic performance of Nd/ TiO2 and Nb/ TiO2 nanomaterials in the degradation of p-cresol at room temperature. J. Chem. Technol. Biotechnol., 2024, 10.1002/jctb.7624.
Rudakova, A.V., Bulanin, K.M., Photoinduced superhydrophilicity of titanium dioxide: effect of heterovalent doping with metals. Colloid J. 86 (2024), 757–779, 10.1134/S1061933X24600544.
Zhang, M., Lu, D., Zhang, Z., Yang, J., Enhancement of visible-light-induced photocurrent and photocatalytic activity of V and N codoped TiO 2 nanotube array films. J. Electrochem. Soc. 161 (2014), H416–H421, 10.1149/2.119406jes.
N. Kumari, K. Gaurav, R. Dash, A.S. Bhattacharyya, Doped mixed phase transition metal oxides for photocatalysis, in: Handbook of Emerging Materials for Sustainable Energy, Elsevier, 2024: pp. 333–346. https://doi.org/10.1016/B978-0-323-96125-7.00004-6.
An Doong, R., Chang, P.Y., Huang, C.H., Microstructural and photocatalytic properties of sol-gel-derived vanadium-doped mesoporous titanium dioxide nanoparticles. J. Non Cryst. Solids 355 (2009), 2302–2308, 10.1016/j.jnoncrysol.2009.07.017.
Safiay, N.M., Khusaimi, Z., Asib, N.A.M., Rani, R.A., Azhar, N.E.A., Hamzah, F., Rusop, M., Nb-doped, V.-L., TiO2 nanoparticles synthesized via facile sol-gel method. 2019 IEEE Regional Symposium on Micro and Nanoelectronics (RSM), 2019, IEEE, Pahang, 57–60, 10.1109/RSM46715.2019.8943501.
Paul, R., K., K., S., P., Tantalum doped titanium dioxide nanoparticles for efficient photocatalytic degradation of dyes. J. Mol. Struct., 1277, 2023, 10.1016/j.molstruc.2022.134869.
Monfort, O., Petrisková, P., Binary and ternary vanadium oxides: General overview, physical properties, and photochemical processes for environmental applications. Processes 9 (2021), 1–57, 10.3390/pr9020214.
Favet, T., Sharna, S., Keller, V., El Khakani, M.A., Cottineau, T., (M,N) codoping (M = Nb or Ta) and CoO nanoparticle decoration of TiO2 nanotubes: synergistic enhancement of visible photoelectrochemical water splitting. Mater. Today Energy, 37, 2023, 10.1016/j.mtener.2023.101376.
Prabhakarrao, N., Rao, T.S., Lakshmi, K.V.D., Divya, G., Jaishree, G., Raju, I.M., Alim, S.A., Enhanced photocatalytic performance of Nb doped TiO2/reduced graphene oxide nanocomposites over rhodamine B dye under visible light illumination. Sust. Environ. Res., 31, 2021, 10.1186/s42834-021-00110-x.
Hsu, C.H., Te Chen, K., Lin, L.Y., Wu, W.Y., Liang, L.S., Gao, P., Qiu, Y., Zhang, X.Y., Huang, P.H., Lien, S.Y., Zhu, W.Z., Tantalum-doped TiO2 prepared by atomic layer deposition and its application in perovskite solar cells. Nanomaterials, 11, 2021, 10.3390/nano11061504.
Mahy, J.G., Lambert, S.D., Léonard, G.-L.-M., Zubiaur, A., Olu, P.-Y., Mahmoud, A., Boschini, F., Heinrichs, B., Towards a large scale aqueous sol-gel synthesis of doped TiO2: Study of various metallic dopings for the photocatalytic degradation of p-nitrophenol. J. Photochem. Photobiol. A Chem. 329 (2016), 189–202, 10.1016/j.jphotochem.2016.06.029.
Chahal, S., Phor, L., Singh, S., Singh, A., Malik, J., Goel, P., Kumar, A., Kumar, S., Ankita, P. Kumar, An efficient and unique method for the growth of spindle shaped mg-doped cerium oxide nanorods for photodegradation of p-nitrophenol. Ceram. Int. 48 (2022), 28961–28968, 10.1016/j.ceramint.2022.04.145.
M.C. Wu, T.H. Lin, J.S. Chih, K.C. Hsiao, P.Y. Wu, Niobium doping induced morphological changes and enhanced photocatalytic performance of anatase TiO2, in: Jpn J Appl Phys, Japan Society of Applied Physics, 2017. https://doi.org/10.7567/JJAP.56.04CP07.
Farcy, A., Mahy, J.G., Alié, C., Caucheteux, J., Poelman, D., Yang, Z., Eloy, P., Body, N., Hermans, S., Heinrichs, B., Lambert, S.D., Kinetic study of p-nitrophenol degradation with zinc oxide nanoparticles prepared by sol–gel methods. J. Photochem. Photobiol. A Chem., 456, 2024, 10.1016/j.jphotochem.2024.115804.
Ramos-Delgado, N.A., Pino-Sandoval, D.A., López-Velázquez, K., Englezos, C., Villanueva-Rodríguez, M., Gracia-Pinilla, M.A., Boscher, N.D., Gardeniers, H.J.G.E., Susarrey-Arce, A., Acetaminophen oxidation under solar light using Fe-BiOBr as a mild Photo-Fenton catalyst. J. Photochem. Photobiol. A Chem., 446, 2024, 10.1016/j.jphotochem.2023.115124.
Ranjan, R., Prakash, A., Singh, A., Singh, A., Garg, A., Gupta, R.K., Effect of tantalum doping in a TiO2 compact layer on the performance of planar spiro-OMeTAD free perovskite solar cells. J Mater Chem A Mater 6 (2018), 1037–1047, 10.1039/c7ta09193a.
Liu, B., Wang, X., Cai, G., Wen, L., Song, Y., Zhao, X., Low temperature fabrication of V-doped TiO2 nanoparticles, structure and photocatalytic studies. J. Hazard. Mater. 169 (2009), 1112–1118, 10.1016/j.jhazmat.2009.04.068.
Da Silva, A.L., Muche, D.N.F., Dey, S., Hotza, D., Castro, R.H.R., Photocatalytic Nb2O5-doped TiO2 nanoparticles for glazed ceramic tiles. Ceram. Int. 42 (2016), 5113–5122, 10.1016/j.ceramint.2015.12.029.
Malengreaux, C.M., Pirard, S.L., Léonard, G., Mahy, J.G., Herlitschke, M., Klobes, B., Hermann, R., Heinrichs, B., Bartlett, J.R., Study of the photocatalytic activity of Fe3+, Cr3+, La3+and Eu3+single-doped and co-doped TiO2 catalysts produced by aqueous sol-gel processing. J. Alloy. Compd. 691 (2017), 726–738, 10.1016/j.jallcom.2016.08.211.
Wang, B., Zhang, G., Leng, X., Sun, Z., Zheng, S., Characterization and improved solar light activity of vanadium doped TiO2/diatomite hybrid catalysts. J. Hazard. Mater. 285 (2015), 212–220, 10.1016/j.jhazmat.2014.11.031.
Cui, Q., Zhao, X., Lin, H., Yang, L., Chen, H., Zhang, Y., Li, X., Improved efficient perovskite solar cells based on Ta-doped TiO2 nanorod arrays. Nanoscale 9 (2017), 18897–18907, 10.1039/c7nr05687g.
Mahy, J.G., Deschamps, F., Collard, V., Jérôme, C., Bartlett, J., Lambert, S.D., Heinrichs, B., Acid acting as redispersing agent to form stable colloids from photoactive crystalline aqueous sol–gel TiO2 powder. J Solgel Sci. Technol. 87 (2018), 568–583, 10.1007/s10971-018-4751-6.
Wang, T., Xu, T., Effects of vanadium doping on microstructures and optical properties of TiO2. Ceram. Int. 43 (2017), 1558–1564, 10.1016/j.ceramint.2016.10.132.
Chen, Y.W., Chang, J.Y., Moongraksathum, B., Preparation of vanadium-doped titanium dioxide neutral sol and its photocatalytic applications under UV light irradiation. J. Taiwan Inst. Chem. Eng. 52 (2015), 140–146, 10.1016/j.jtice.2015.02.006.
Kong, L., Wang, C., Zheng, H., Zhang, X., Liu, Y., Defect-induced yellow color in Nb-doped TiO2 and its impact on visible-light photocatalysis. J. Phys. Chem. C 119 (2015), 16623–16632, 10.1021/acs.jpcc.5b03448.
Kumaravel, V., MacCioni, M.B., Mathew, S., Hinder, S.J., Bartlett, J., Nolan, M., Pillai, S.C., Unravelling the impact of ta doping on the electronic and structural properties of titania: a combined theoretical and experimental approach. J. Phys. Chem. C 126 (2022), 2285–2297, 10.1021/acs.jpcc.1c10805.
Shukla, S., Manwani, K., Patel, T.A., Panda, E., Thin highly transparent visible/near-infrared Ta-doped TiO2 electrode. J. Mater. Sci. Mater. Electron., 34, 2023, 10.1007/s10854-022-09672-x.
Kniec, K., Ledwa, K., Marciniak, L., Enhancing the relative sensitivity of V5+, V4+ and V3+ based luminescent thermometer by the optimization of the stoichiometry of Y3Al5-xGaxO12 nanocrystals. Nanomaterials, 9, 2019, 10.3390/nano9101375.
Alim, M.A., Bak, T., Atanacio, A.J., Ionescu, M., Kennedy, B., Price, W.S., Du Plessis, J., Pourmahdavi, M., Zhou, M., Torres, A., Nowotny, J., Photocatalytic properties of Ta-doped TiO2. Ionics (Kiel) 23 (2017), 3517–3531, 10.1007/s11581-017-2162-2.
Li, L., Yan Liu, C., Liu, Y., Study on activities of vanadium (IV/V) doped TiO2 (R) nanorods induced by UV and visible light. Mater Chem Phys 113, 2009, 551–557, 10.1016/j.matchemphys.2008.08.009.
Lee, J., Lu, W., Kioupakis, E., Electronic properties of tantalum pentoxide polymorphs from first-principles calculations. Appl. Phys. Lett., 105, 2014, 10.1063/1.4901939.
Su, K., Liu, H., Gao, Z., Fornasiero, P., Wang, F., Nb2O5-Based Photocatalysts. Adv. Sci., 8, 2021, 10.1002/advs.202003156.
Sudrajat, H., Hartuti, S., Babel, S., Mechanistic understanding of the increased photoactivity of TiO2 nanosheets upon tantalum doping. PCCP 24 (2022), 995–1006, 10.1039/d1cp03907e.
Mendez, M.S., Lemarchand, A., Traore, M., Perruchot, C., Sassoye, C., Selmane, M., Nikravech, M., Ben Amar, M., Kanaev, A., Photocatalytic activity of nanocoatings based on mixed oxide v- TiO2 nanoparticles with controlled composition and size. Catalysts, 11, 2021, 10.3390/catal11121457.
Ozawa, K., Emori, M., Yamamoto, S., Yukawa, R., Yamamoto, S., Hobara, R., Fujikawa, K., Sakama, H., Matsuda, I., Electron-hole recombination time at TiO2 single-crystal surfaces: Influence of surface band bending. J. Phys. Chem. Lett. 5 (2014), 1953–1957, 10.1021/jz500770c.
Yeager, E., DIOXYGEN ELECTROCATALYSIS: MECHANISMS IN RELATION TO CATALYST STRUCTURE. The 1985 Berzelius Lecture. J. Mol. Catal. 38:1986 (1985), 5–25.
Pignatello, J.J., Oliveros, E., MacKay, A., Advanced oxidation processes for organic contaminant destruction based on the fenton reaction and related chemistry. Crit. Rev. Environ. Sci. Technol. 36 (2006), 1–84, 10.1080/10643380500326564.
Zhao, G., Li, H., Zhang, J., Chen, Z., Han, G., Song, B., Effects of preparation parameters on room temperature formation of vanadium-doped TiO2 nanocrystalline powder. J. Am. Ceram. Soc. 94 (2011), 71–76, 10.1111/j.1551-2916.2010.04033.x.
Sacco, O., Sannino, D., Matarangolo, M., Vaiano, V., Room temperature synthesis of V-Doped TiO2 and its photocatalytic activity in the removal of caffeine under UV Irradiation. Materials, 12, 2019, 10.3390/ma12060911.
Wang, C., Geng, A., Guo, Y., Jiang, S., Qu, X., Three-dimensionally ordered macroporous Ti1-xTaxO2+x/2 (x = 0.025, 0.05, and 0.075) nanoparticles: Preparation and enhanced photocatalytic activity. Mater. Lett. 60 (2006), 2711–2714, 10.1016/j.matlet.2006.01.109.
Falk, G.S., Borlaf, M., López-Muñoz, M.J., Rodrigues Neto, J.B., Moreno, R., Photocatalytic activity of nanocrystalline TiNb2O7 obtained by a colloidal sol-gel route. Ceram. Int. 44 (2018), 7122–7127, 10.1016/j.ceramint.2018.01.153.