Paper
RSC Advances
metal ions is dried and sintered aer all impurities are removed
by the dialysis. Furthermore, metal ions having similar ionic
size as Ti(IV) interact with TiO2 nanoparticles because they
remain but larger metal ions such as Cu(II) are lost in the TiO2
A. Debut, D. C. Whitehead and F. Alexis, RSC Adv., 2020,
10, 7967–7975.
9 W. Qu, P. Wang, M. Gao, J. Hasegawa, Z. Shen, Q. Wang, R. Li
and D. Zhang, Environ. Sci. Technol., 2020, 54, 9693–9701.
sol during the dialysis. Our ndings indicate that the different 10 R. Magudieshwaran, J. Ishii, K. Chandar, N. Raja,
dependence of the degradation rate of CH
3
CHO on the doping
C. Terashima, R. Venkatachalam, A. Fujishima and
amounts of Cr–TiO , Pt–TiO and V–TiO is attributable to their
2
2
2
S. Pitchaimuthu, Mater. Lett., 2019, 239, 40–44.
main valence states which are correlated with the formation of 11 A. H. Mamaghani, F. Haghighat and C. Lee, Chemosphere,
the oxygen vacancies. Recently, the oxygen vacancies have 2019, 219, 804–825.
attracted much attention because they are believed to play an 12 I. Wysocka, A. Markowska-Szczupak, P. Szweda, J. Ryl,
important role to improve the photocatalytic activity. They can
M. Endo-Kimura, E. Kowalska, G. Nowaczyk and
be created by sintering TiO at high temperatures in an oxygen-
A. Zielinska-Jurek, Indoor Air, 2019, 29, 979–992.
2
poor atmosphere but disappear slowly when being exposed to 13 V. Menendez-Flores and T. Ohno, Catal. Today, 2014, 230,
2
8
air. However, it is very difficult to discuss the oxygen vacancies
in TiO doped with other elements because crystal lattice might 14 X. Yang, C. Cao, K. Hohn, L. Erickson, R. Maghirang,
be distorted by forming several point defects such as Ti inter- D. Hamal and K. Klabunde, J. Catal., 2007, 252, 296–302.
stitial, oxygen vacancies, and interstitial or substitutional 15 N. Nishiyama, Y. Fujiwara, K. Adachi, K. Inumaru and
impurities including dopant ions. The present results suggest S. Yamazaki, Appl. Catal., B, 2015, 176–177, 347–353.
that Cr(III) in Cr–TiO2 stabilizes the formation of oxygen 16 S. Yamazaki, D. Takaki, N. Nishiyama, and Y. Yamazaki, in
214–220.
2
vacancies. The Cr–TiO powder synthesized in this study might
be promising to elucidate the role of oxygen vacancies in
photocatalysis.
Current Developments in Photocatalysis and Photocatalytic
Materials, ed. X. Wang, M. Anpo, and X. Fu, Elsevier, 2019,
pp. 23–38.
2
1
1
1
2
7 P. Makula, M. Pacia and W. Macyk, J. Phys. Chem. Lett., 2018,
9
, 6814–6817.
Conflicts of interest
8 T. T. Loan, V. H. Huong, V. T. Tham and N. N. Long, Phys. B,
2018, 532, 210–215.
9 X. Yu, J. Xie, H. Dong, Q. Liu and Y. Li, Chem. Phys. Lett.,
There are no conicts to declare.
2020, 754, 137732.
Acknowledgements
0 S. P. Takle, O. A. Apine, J. D. Ambekar, S. L. Landge,
N. N. Bhujbal, B. B. Kale and R. S. Sonawane, RSC Adv.,
2019, 9, 4226–4238.
This work was supported by JSPS KAKENHI Grant 18K05298.
We thank Yamaguchi University Science Research Center for
the ICP-OES and XRD measurements. We appreciate Mr T. 21 G. Rossi, L. Pasquini, D. Catone, A. Piccioni, N. Patelli,
Tonosaki for the technical support on the XPS measurements at
Collaborative Center for Engineering Research Equipment,
Faculty of Engineering, Yamaguchi University.
A. Paladini, A. Molinari, S. Caramori, P. O'Keeffe and
F. Boscherini, Appl. Catal., B, 2018, 237, 603–612.
22 S. Kim, S. Hwang and W. Choi, J. Phys. Chem. B, 2005, 109,
24260–24267.
2
3 R. D. Shannon, Acta Crystallogr., Sect. A: Cryst. Phys., Diffr.,
Theor. Gen. Crystallogr., 1976, 32, 751–767.
Notes and references
1
E. S. Karafas, M. N. Romanias, V. S. Stefanopoulos, V. Binas, 24 X. Chen, C. Meng, Y. Wang, Q. Zhao, Y. Li, X. Chen, D. Yang,
A. Zachopoulos, G. Kiriakidis and P. Papagiannakopoulos, J.
Photochem. Photobiol., A, 2019, 371, 255–263.
Y. Li and Y. Zhou, ACS Sustainable Chem. Eng., 2020, 8, 1095–
1101.
2
3
S. Izadyar and S. Fatemi, Ind. Eng. Chem. Res., 2013, 52, 25 F. Yang, R. Yang, L. Yan, X. Liu, X. Luo and L. Zhang, Catal.
0961–10968.
Sci. Technol., 2020, 10, 5659–5665.
T. Takigawa, B. Wang, Y. Saijo, K. Morimoto, K. Nakayama, 26 J. Li, H. Zhuo, Z. Wei, G. Zhuang, X. Zhong, S. Deng, X. Li and
M. Tanaka, E. Shibata, T. Yoshimura, H. Chikara, K. Ogino J. Wang, J. Mater. Chem. A, 2018, 6, 2264–2272.
and R. Kishi, Int. Arch. Occup. Environ. Health, 2010, 83, 27 B. B. Adormaa, W. K. Darkwah and Y. Ao, RSC Adv., 2018, 8,
25–235. 33551–33563.
F. Salvadores, R. I. Minen, J. Carballada, O. M. Alfano and 28 Q. Wu, Q. Zheng and R. Krol, J. Phys. Chem. C, 2012, 116,
M. M. Ballari, Chem. Eng. Technol., 2016, 39, 166–174. 7219–7226.
H. Ichimura, T. Seike and A. Kozu, Chemosphere, 2020, 256, 29 A. Naldoni, M. Altomare, G. Zoppellaro, N. Liu, S. Kment,
27143.
R. Zboril and P. Schmuki, ACS Catal., 2019, 9, 345–364.
S. Weon and W. Choi, Environ. Sci. Technol., 2016, 50, 2556– 30 F. Ren, H. Li, Y. Wang and J. Yang, Appl. Catal., B, 2015, 176–
563. 177, 160–172.
V. Kumar, Y. Lee, J. Shin, K. Kim, D. Kukkar and Y. F. Tsang, 31 N. Nishiyama and S. Yamazaki, ACS Omega, 2017, 2, 9033–
Environ. Int., 2020, 135, 105356. 9039.
I. Bravo, F. Figueroa, M. I. Swasy, M. F. Attia, M. Ateia, 32 B. D. Mukri, U. V. Waghmare and M. S. Hegde, Chem. Mater.,
D. Encalada, K. Vizuete, S. Galeas, V. H. Guerrero, 2013, 25, 3822–3833.
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6
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