Abstract
Nb-doped TiO2 thin-films were prepared on fluorine-doped tin oxide (FTO) coated glass directly with niobium ethoxide and TiCl4 in water under the acidic conditions with several concentrations of HCl at 70–90 °C for 45 minutes or 1 hour followed by rinsing with water and annealing at 100 °C for 1 hour. Thin films of 0–1% Nb-doped TiO2 with rutile phase on FTO were obtained, which were confirmed through X-ray diffraction analyses and measurements of energy dispersive X-ray spectroscopy (EDS). Scanning electron microscopy observations equipped with EDS revealed that higher growth temperature over 90 °C is required for doping of Nb. While higher concentration of HCl resulted in much amount of Nb-doping. Band gap of rutile TiO2 gradually reduced from 3.3 eV to 3.23 eV through Nb-doping from 0% to 1%, which were estimated from uv-vis absorption spectroscopic analyses. Hall effect measurements by taking van der Pauw method confirmed that 2.26 times increase of the carrier density and 1.78 times enhancement of the conductivity have been achieved in the case of 1% Nb-doping.
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P. Cheng, S. Du, Y. Cai, F. Liu, P. Sun, J. Zheng, and G. Lu, J. Phys. Chem. C 117, 24150–24156 (2013).
C. Liu, R. Zhu, A. Ng, Z. Ren, S. H. Cheung, L. Du, S. K. So, J. A. Zapien, A. B. Djurisic, D. L. Phillips, and C. Surya, J. Mater. Chem. A 5, 15970–15980 (2017).
M. Mallak, M. Bockmeyer, and P. Löbmann, Thin Solid Films 515, 8072–8077 (2007).
A.V. Manole, M. Dobromir, M. Gîrtan, R.Mallet, G.Rusu, and D. Luca, Ceramics International 39, 4771–4776 (2013).
C. Liang, Z. Wu, P. Li, J. Fan, Y. Zhang, and G. Shao, Applied Surface Science 391, 337–344 (2017).
Y. Xu, C. Gao, S. Tang, J. Zhang, Y. Chen, Y. Zhu, and Z. Hu, J. Alloys and Compounds 787, 1082–1088 (2019).
P. M. Sommeling, B. C. O’Regan, R. R. Haswell, H. J. P. Smit, N. J. Bakker, J. J. T. Smits, J. M. Kroon, and J. A. M. van Roosmalen, J. Phys. Chem. B 110, 19191–19197 (2006).
B. Liu and E. S. Aydil J. Am. Chem. Soc. 131, 3985–3990 (2009)
Y. Ko, Y. Kim, S. Y. Kong, S. C. Kunnana, and Y. Jun, Solar Energy Materials and Solar Cells 183, 157–163 (2018).
U. K. Thakur, R. Kisslinger, and K. Shankar, Nanomaterials 7, 95 (2017).
R. Shannon, Acta Crystallogr. Sect. A 32, 751 (1976).
J. Song, S. P. Li, Y. L. Zhao, J. Yuan, Y. Zhu, Y. Fang, L. Zhu, X. Q. Gu, and Y. H. Qiang, J. Alloys and Compounds 694, 1232–1238 (2017).
Y. Pang and P. Wynblatt, J. Am. Ceram. Soc. 89, 666–671 (2006).
Y. Li, Y. Guo, Y. Li, and X. Zhou, Electrochimica Acta 200, 29–36 (2016).
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Kimura, T., Hachiya, K. & Sagawa, T. Nb-doped TiO2 Thin Films Prepared through TiCl4 Treatment for Improvement of Their Carrier Transport Property. MRS Advances 4, 2665–2671 (2019). https://doi.org/10.1557/adv.2019.425
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DOI: https://doi.org/10.1557/adv.2019.425