Role of Na+ ion removal on the photocatalytic properties of hydrothermally-prepared nanotubes TiO2

Naimat Abimbola Eleburuike, Wan Azelee Wan Abu Bakar, Rusmidah Ali


Nanostructured TiO2 enjoys wide patronage for the remediation of water sources that have been contaminated with organic pollutants due to its excellent photocatalytic properties. This study investigated the role of removal of Na+ ions from hydrothermally-prepared TiO2 nanotubes (TNTs) by washing with dilute hydrochloric acid. The photocatalytic activity of TNTs was tested on the degradation of modelled paraquat dichloride-contaminated water. It was found that the amount of residual Na+ ions after acid washing greatly influenced the photocatalytic properties of TNTs. The Na+ ions had significant effect on the crystal structure of TNTs and the crystal structure varied with the annealing temperature. Hence, the effect of the residual Na+ ions was observed at different annealing temperatures of 500, 700 and 800 °C. It was discovered that TNTs containing negligible Na+ ions demonstrated high photocatalytic activity at 500 °C annealing temperature because it consisted of active crystalline anatase species at this temperature. On the other hand, TNTs with high Na+ ion content showed poor performance at 500 °C due to the presence of amorphous sodium titanate species which could result in rapid electron-hole pair recombination. So, it showed highest photocatalytic activity at 800 °C when the crystallinity had increased. Generally, it can be concluded that TNTs with negligible Na+ ion content demonstrated excellent photocatalytic activity by achieving 77.1% degradation of paraquat dichloride compared to those with high Na+ ion content which achieved 61.1% degradation of paraquat dichloride within 5 h.


Sodium ion, Titanium dioxide, Nanotubes, Photocatalysis, Paraquat dichloride

Full Text:



Eleburuike, N. A., Bakar, W. A. W. A., Ali, R., Omar, M. F. 2016.

Photocatalytic degradation of paraquat dichloride over CeO2-modified TiO2 nanotubes and the optimization of parameters by response surface methodology, RSC Adv., 106, 104082-104093.

Fujishima, A., Rao T., Tryk, D. 2000. Titanium dioxide photocatalysis. J. Photochem. Photobiol. C, 1, 1–21.

GÓrska, P. Zaleska, A., Kowalska, E., Klimczuk, T., Sobczak, J. W., Skwarek, E., Janusz W., Hupka, J. 2008. TiO2 photoactivity in VIS and UV light: The influence of calcination temperature and surface properties. Appl. Catal. B, 84, 440 – 447.

Hanaor, D. A. H., Sorrell, C. C. 2011, Review of the anatase to rutile phase transformation. J. Mater. Sci., 46, 855-874.

Jia, H., Zheng, Z., Zhao, H., Zhang, L., Zou, Z. 2009. Nonaqueous sol–gel synthesis and growth mechanism of single crystalline TiO2 nanorods with high photocatalytic activity. Mater. Research Bulletin, 44, 1312-1316.

Joo, J., Kwon, S., Yu, T., Cho, M., Lee, J., Yoon, J., Hyeon, T. 2005. Large-scale synthesis of TiO2 nanorods via nonhydrolytic sol-gel ester elimination reaction and their application to photocatalytic inactivation of E. coli. J Phys. chem. B, 109, 15297–15302.

Li, Y., Guo, M., Zhang, M., Wang, X. 2009. Hydrothermal synthesis and characterization of TiO2 nanorod arrays on glass substrates. Mater. Research Bulletin, 44 (6), 1232-1237.

Liu, W., Gao, J., Zhang, F., Zhang G. 2007. Preparation of TiO2 nanotubes and their photocatalytic properties in the degradation of methylcyclohexane. Mater. Trans, 48, 2464-2466.

Melcarne, L. Marco, E. Carlino, F. Martina, M. Manca, R. Cingolani, G. Gigli, G., Ciccarella G. 2010. Surfactant -free synthesis of pure anatase TiO2 nanorods suitable for dye-sensitized solar cells. J. Mater. Chem., 20, 7248–7254.

Nolan, N. T., Seery, M. K., Pillai, S. C. 2009. Spectroscopic investigation of the anatase-to-rutile transformation of sol-gel synthesized TiO2 photocatalysts. J. Phys. Chem. C, 113, 16151-16157.

Pesticide Action Network (PAN) Germany. 2003. Paraquat Exposure and Parkinsons’s Disease. Retrieved from PAN Germany website:

Neumeister, L., Isenring, R. 2011. Paraquat: Unacceptable health risks for users. 3rd Edition. Berne Declaration (BD), Pesticide Action Network UK (PAN UK) and Pesticide Action Network Asia & the Pacific (PAN AP), 15–36.

Qamar, M., Yoon, C. R., Oh, H. J., Lee, N. H., Park, K., Kim, D. H., Lee, K. S., Lee, W. J., Kim S. J. 2008. Preparation and photocatalytic activity of nanotubes obtained from titanium dioxide. Catal. Today, 131, 3-14.

Reidy, D. J., Holmes, J. D., Morris, M. A. 2006. The critical size mechanism for the anatase to rutile transformation in TiO2 and doped-TiO2. J. European Ceramic Soc. 26, 1527-1534.

Roy, P., Berger, S., Schmuki, P. 2011. TiO2 Nanotubes: Synthesis and applications. Angewandte Chemie, 50, 2904–2939.

Scanlon, D. O., Dunnill, C. M., Buckeridge, J., Shevlin, S. A., Logsdail, A. J., Woodley, S. M., Catlow, C. R. A., Powell, M. J., Palgrave, R. G., Parkin, I. P., Watson, G. W., Keal, T. W., Sherwood, P., Walsh A., Sokol, A. A. 2013. Band alignment of rutile and anatse TiO2. Nature Mater., 12, 798–801.

Sing, K. S. W. 1982. Reporting physisorption data for gas/solid systems – with special reference to the determination surface area and porosity. Pure Appl. Chem., 54, 2201-2218.

Singh, S., Mahalingam, H., Singh, P. 2013. Polymer-supported titanium dioxide photocatalysts for environmental remediation: A review. Appl. Catal. A, 462-463, 178-195.

Song, S., Tu, J., He Z., Hong, F., Liu, W., Chen, J. 2010. Visible light-driven iodine-doped titanium dioxide nanotubes prepared by hydrothermal process and post-calcination. Appli. Catal. A, 378, 169-174.

Tan., Y. H., Davis, J. A., Fujikawa, K., Ganesh, N. V., Demchenko A. V., Stine, K. J. 2012. Surface area and pore size characteristics of nanoporous gold subjected to high thermal, mechanical, or surface modification studied using gas adsorption isotherms, cyclic voltammetry, thermogravimetric analysis, and scanning electron microscopy, J. Mater. Chem., 22, 6733-6745.

Tsai, C., Teng, H. 2004. Regulation of the physical characteristics of titania nanotube aggregates synthesized from hydrothermal treatment. Chem. Mater., 16, 4352-4358.

Wang, H. E., Chen, Z., Leung, Y., Luan, C., Liu, C. Tang, Y., Yan, C., Zhang, W., Zapien, J., Bello, I., Lee, S. T. 2010. Hydrothermal synthesis of ordered single-crystalline rutile TiO2 nanorod arrays on different substrates. Appl. Phys. Lett., 96, 263-264.

Watts, M. 2012. Highly hazardous pesticides: Paraquat. PAN AP Factsheet Series; Pesticide Action Network Asia and the Pacific, 1–2.

Wu, D., Liu, J., Zhao, X., Li, A., Chen Y., Ming, N. 2006. Sequence of events for the formation of titanate nanotubes, nanofibres, nanowires and nanobelts. Chem. Mater., 18, 547-553.

Yu, J. G., Yu, H. G., Cheng, B., Zhao, X. J., Yu, J. C., Ho, W. K. 2003. The effect of calcination temperature on the surface microstructure and photocatalytic activity of TiO2 thin films prepared by liquid phase deposition. J. Phys. Chem. B, 107, 13871-13879.



  • There are currently no refbacks.

Copyright (c) 2017 Naimat Abimbola Eleburuike, Wan Azelee Wan Abu Bakar, Rusmidah Ali

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Copyright © 2016 Penerbit UTM Press, Universiti Teknologi Malaysia. Disclaimer: This website has been updated to the best of our knowledge to be accurate. However, Universiti Teknologi Malaysia shall not be liable for any loss or damage caused by the usage of any information obtained from this website.