- Email: [email protected]
High UV-visible photocatalytic activity of Ag3PO4 dodecahedral particles synthesized by a simple hydrothermal method
Materials Letters 201 (2017) 58–61
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
High UV-visible photocatalytic activity of Ag3PO4 dodecahedral particles synthesized by a simple hydrothermal method Saowalak Krungchanuchat a, Nuengruethai Ekthammathat b,⇑, Anukorn Phuruangrat c,⇑, Somchai Thongtem d,e, Titipun Thongtem a,⇑ a
Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand Program of Chemistry, Faculty of Science and Technology, Bansomdejchaopraya Rajabhat University, Bangkok 10600, Thailand Department of Materials Science and Technology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand d Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand e Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand b c
a r t i c l e
i n f o
Article history: Received 19 February 2017 Received in revised form 26 April 2017 Accepted 27 April 2017 Available online 29 April 2017 Keywords: Ag3PO4 Dodecahedral particles Photocatalysis
a b s t r a c t Silver phosphate (Ag3PO4) was successfully synthesized in the solutions with pH of 8 by a hydrothermal method at 100–200 °C and a precipitation method at room temperature (ca 32 °C) without any surfactant adding. Phase, morphology and vibrational modes of the products were characterized by XRD, FE-SEM and FTIR. Only morphology and crystalline degree were controlled by the synthetic methods and conditions. In this research, Ag3PO4 was found to have the potential in photocatalytic degradation of organic rhodamine B (RhB) dye molecules. The photocatalytic activity of Ag3PO4 dodecahedral particles synthesized by the 150 °C and 24 h hydrothermal reaction has the highest activity of 99.55% in decolorizing of RhB under UV light within 120 min. Ó 2017 Elsevier B.V. All rights reserved.
1. Introduction The degradation of organic contaminants in waste water by photocatalysts has been extensively studied [1]. There are many parameters that can play the role in the properties of photocatalysts: size/nanosize [2–4], energy gap [5], morphology [3] and crystalline degree. One of several photocatalysts, silver (ortho) phosphate (Ag3PO4) is now very interesting for researchers. It has high efficiency over 380–780 nm visible range of the solar spectrum [6]. It is an active semiconductor in photo-oxidation, high activity with absorbance in the visible light and high charged carrier mobility. It has the lowest delocalized charge distribution in conduction band, low electron effective mass and benefit of surface carrier mobility [6,7]. The Ag3PO4 novel semiconductor has quantum efficiency of 90% [6–8] at a wavelength longer than 420 nm [6,8] and has demonstrated the excellent photocatalytic ability for oxidation of water and degradation of organic contaminants in aqueous solution under visible radiation [2,9]. Accordingly, the materials can be synthesized by different methods: hydrothermal [1], ion-exchange [2,5,7] and thermolysis [3,4,10]. In this research, ⇑ Corresponding authors. E-mail addresses: [email protected] (T. Thongtem).
[email protected] (N. Ekthammathat), (A. Phuruangrat), [email protected]
http://dx.doi.org/10.1016/j.matlet.2017.04.131 0167-577X/Ó 2017 Elsevier B.V. All rights reserved.
Ag3PO4 synthesized by precipitation and hydrothermal methods using different synthetic conditions was discussed and the photocatalytic properties were evaluated through the degradation of Rhodamine B (RhB) organic dye molecules.
2. Experiment All reagents were analytical grade and used without further purification. 0.003 mol Na3PO4 and 0.003 mol AgNO3 were separately dissolved in 40 ml DI water each to form two precursor solutions, which were mixed together. The mixed solution was adjusted the pH to 8 by HNO3, stirred at room temperature for 15 min, and hydrothermally processed at 100, 150 and 200 °C for 24 h. Concurrently, the mixed solution was stirred at room temperature (RT ca 32 °C) for 3 h. In the end, the as-synthesized precipitates by hydrothermal and precipitation reactions were separated by filtration, washed with DI water and ethanol, and dried at 70 °C for 24 h for further characterization. Phase and crystalline degree were characterized by an X-ray diffractometer (XRD, Philips X’Pert MPD) using a Cu Ka radiation at 45 kV and 35 mA in the range of 20–75°. The functional/compositional groups of the products diluted with KBr for 40 times were analyzed by a Fourier transform infrared spectrometer (FTIR, Perkin Elmer RX spectrophotometer) over 400–4000 cm–1 range with
S. Krungchanuchat et al. / Materials Letters 201 (2017) 58–61
4 cm–1 resolution. The morphologies were investigated by a field emission scanning electron microscope (FE-SEM, JEOL JSM6335F) operating at 35 kV. Photocatalytic activity of the as-synthesized Ag3PO4 was evaluated through the degradation of RhB in an aqueous solution under UV radiation. 0.15 g photocatalyst was dispersed in 150 ml of 10–5 M RhB aqueous solution, which were stirred in the dark for 30 min to establish an adsorption-desorption equilibrium of RhB on the surface of photocatalyst. Then the light was turned on to initiate photocatalysis. The 5 ml solution was sampled every 20 min and analyzed by a UV-visible spectrometer (Perkin Elmer Lambda
59
25). Photocatalysis was proceeding in a photo-reactor equipped with three 15 W UV germicidal irradiation lamps. Decolorization efficiency (%) was calculated by [(C0 C)/C0] 100, where C0 is the initial concentration of RhB and C is the concentration of RhB after light irradiation. 3. Results and discussion The XRD patterns (Fig. 1a) indicated the phase and crystalline degree of different products corresponding to cubic silver phosphate (Ag3PO4) with lattice parameter of 6.0130 Å and P43n space
Fig. 1. (a) XRD patterns and (b) FTIR spectra of Ag3PO4 synthesized in the solutions with the pH of 8 by precipitation at RT for 3 h and by hydrothermal method at 100, 150 and 200 °C for 24 h.
Fig. 2. SEM images of Ag3PO4 synthesized in the solutions with the pH of 8 by (a) precipitation at RT for 3 h and (b–d) hydrothermal method at 100, 150 and 200 °C for 24 h, respectively.
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group (JCPDS No. 06-0505) [11]. The average crystal size calculated by Scherrer formula [12] was 154–166 nm. The intensities of all XRD peaks were increased with the increase of reaction temperature from RT to 150 °C, and remained unchanged at 200 °C. The crystalline degree was not significantly increased although the synthetic temperature was higher than 150 °C. Thus, the highest crystalline degree was obtained at 150 °C. In this research, the solid material was separated from a liquid only in basic solution, and Ag3PO4 precipitated as pure product in the solution with the pH of 8. Fig. 1b shows the FTIR spectra of Ag3PO4 synthesized at RT, 100 °C and 150 °C over the range of 400–4000 cm–1. Strong bands centered at 555 cm–1 were assigned as the O@PAO bending vibration and at 1010 cm–1 as the asymmetric stretching of (PO4)3 groups [12]. The 1650 cm–1 band is due to H2O bending mode. The absorption band at 3400–3650 cm–1 is related to the stretching vibration of adsorbed water [2,13,14]. The products synthesized at different conditions were characterized by SEM (Fig. 2). At RT precipitation for 3 h, Ag3PO4 was composed of a number of nanoparticles with 100–200 nm in diameter. They were clustered together in groups with different orientations. For the hydrothermal reaction at 100 °C for 24 h, the size of the product was increased and remained as clusters with 250– 1000 nm diameter. At 150 and 200 °C, the Ag3PO4 products shape like dodecahedrons (a solid figure with twelve flat sides) with the size of 1.5–2 mm and 2–4 mm, respectively. The degradation of RhB as a model organic contaminant at a major absorption band of 553 nm (Fig. 3) shows evolution of the
spectral intensities during the photodegradation of RhB by Ag3PO4 particles synthesized at different conditions under UV radiation. The absorption intensity gradually decreased and the solutions were decolorized from pink into colorless within 120 min. The degradation of RhB by different products has different rates (Fig. 4). Comparing to the blank, the RhB degradation by the assynthesized Ag3PO4 products within 120 min was 98.66, 99.23, 99.55 and 84.23% for the products synthesized at RT, 100 °C, 150 °C and 200 °C, respectively. Photodegradation of the 200 °C product is the lowest. Possibly, the particles are too large to be used for photocatalysis. In this research, Ag3PO4 dodecahedrallike particles synthesized at 150 °C for 24 h is the best promising photocatalyst for photodegradation of RhB. It can degrade RhB very quickly within 120 min by transforming the pink solution into a colorless one. A proposed mechanism can be explained by the production of H2O2 and OH during the photocatalysis. Photogeneration of H2O2 was proceeding throughout the process. Its concentration was increased with increasing in the irradiation time, suggesting that two-electron reduction of dissolved oxygen took place on the Ag3PO4 surface [9]. The reduction potential at the CB level of Ag3PO4 is +0.45 V (vs NHE) [5,9]. Direct electron transfer to oxygen molecules (O2 + e ? O2 ) requires 0.284 V (vs NHE) [5,9] and formation of HO2 (O2 + H+ + e ? HO2 requires 0.046 V) was very difficult. The accumulated electrons in the CBAg3PO4 diffused to oxygen species through the multi-electron processes [5]: O2 + 2H+ + 2e ? H2O2 requires +0.682 V and O2 + 4H+ + 4e ? 2H2O requires +1.23 V [9]. They are higher than the CBAg3PO4
Fig. 3. UV-visible absorption of RhB photocatalyzed by Ag3PO4 synthesized in the solutions with the pH of 8 by (a) precipitation at RT for 3 h and (b–d) hydrothermal reactions at 100, 150 and 200 °C for 24 h, respectively.
S. Krungchanuchat et al. / Materials Letters 201 (2017) 58–61
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at room temperature without any surfactant adding. Ag3PO4 synthesized in the solution with the pH of 8 at 150 °C for 24 h has the highest efficiency (99.55%) in photodegradation of RhB under UV radiation within 120 min. Acknowledgements We wish to thank Chiang Mai University, Thailand for providing financial support through the Center of Excellence in Materials Science; Chiang Mai University (CMU) through the CMU’s 50th Anniversary Ph.D. Grant; and Science and Applied Science Center (SASC), Bansomdejchaopraya Rajabhat University, Thailand through a general support. References
Fig. 4. Decolorization efficiency of RhB photocatalyzed by Ag3PO4 synthesized in the solutions with the pH of 8 by precipitation at RT for 3 h and by hydrothermal reactions at 100, 150 and 200 °C for 24 h comparing with that of the blank.
potential. Furthermore, photogenerated holes tended to remain on the surface of Ag3PO4 due to the large negative charge of PO34 ions which preferred to attract holes and repel electrons. Meanwhile PO34 ions have strong bonding ability with H2O. Thus, H2O could be easily adsorbed on surface and oxidized by the holes to hydroxyl radicals (OH) which eventually degraded the RhB dye to CO2 and H2O [8,15]. 4. Conclusions In summary, Ag3PO4 particles were successfully synthesized by both hydrothermal reaction at high temperature and precipitation
[1] M.Q. Wen, T. Xiong, Z.G. Zhang, W. Wei, X.T. Tang, F. Dong, Opt. Express 24 (2016) 258178. [2] J. Ma, J. Zou, L. Li, C. Yao, T. Zhang, D. Li, Appl. Catal. B 134–135 (2013) 1–6. [3] M. Ramezani, A. Sobhani-Nasab, S.M. Hosseinpour-Mashkani, J. Mat. Sci. Mater. Electron. 26 (2015) 4848–4853. [4] S.M. Hosseinpour-Mashkani, A. Sobhani-Nasab, J. Mat. Sci. Mater. Electron. 28 (2017) 4345–4350. [5] S.B. Rawal, S.D. Sung, W.I. Lee, Catal. Commun. 17 (2012) 131–135. [6] K. Shen, M.A. Gondal, R.G. Siddique, S. Shi, S. Wang, J. Sun, Q. Xu, Chin. J. Catal. 35 (2014) 78–84. [7] X. Yan, Q. Gao, J. Qin, X. Yang, Y. Li, H. Tang, Ceram. Inter. 39 (2013) 9715–9720. [8] Y. Liu, L. Fang, H. Lu, Y. Li, C. Hu, H. Yu, Appl. Catal. B 115–116 (2012) 245–252. [9] H. Katsumata, M. Taniguchi, S. Kaneco, T. Suzuki, Catal. Commun. 34 (2013) 30–34. [10] A. Javidan, M. Ramezani, A. Sobhani-Nasab, S.M. Hosseinpour-Mashkani, J. Mat. Sci. Mater. Electron. 26 (2015) 3813–3818. [11] Powder Diffract. File, JCPDS-ICDD, 12 Campus Bld., Newtown Square, PA 19073–3273, U.S.A., 2001. [12] A. Morato, V. Rives, Appl. Catal. B 202 (2017) 418–419. [13] J. Zhang, H. Bi, G. He, Y. Zhou, H. Chen, J. Environ. Chem. Eng. 2 (2014) 952– 957. [14] A. Wu, C. Tian, W. Chang, Y. Hong, Q. Zhang, Y. Qu, H. Fu, Mater. Res. Bull. 48 (2013) 3043–3048. [15] A. Phuruangrat, P. Dumrongrojthanath, S. Thongtem, T. Thongtem, Mater. Lett. 194 (2017) 114–117.
Contents lists available at ScienceDirect
Materials Letters journal homepage: www.elsevier.com/locate/mlblue
High UV-visible photocatalytic activity of Ag3PO4 dodecahedral particles synthesized by a simple hydrothermal method Saowalak Krungchanuchat a, Nuengruethai Ekthammathat b,⇑, Anukorn Phuruangrat c,⇑, Somchai Thongtem d,e, Titipun Thongtem a,⇑ a
Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand Program of Chemistry, Faculty of Science and Technology, Bansomdejchaopraya Rajabhat University, Bangkok 10600, Thailand Department of Materials Science and Technology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand d Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand e Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand b c
a r t i c l e
i n f o
Article history: Received 19 February 2017 Received in revised form 26 April 2017 Accepted 27 April 2017 Available online 29 April 2017 Keywords: Ag3PO4 Dodecahedral particles Photocatalysis
a b s t r a c t Silver phosphate (Ag3PO4) was successfully synthesized in the solutions with pH of 8 by a hydrothermal method at 100–200 °C and a precipitation method at room temperature (ca 32 °C) without any surfactant adding. Phase, morphology and vibrational modes of the products were characterized by XRD, FE-SEM and FTIR. Only morphology and crystalline degree were controlled by the synthetic methods and conditions. In this research, Ag3PO4 was found to have the potential in photocatalytic degradation of organic rhodamine B (RhB) dye molecules. The photocatalytic activity of Ag3PO4 dodecahedral particles synthesized by the 150 °C and 24 h hydrothermal reaction has the highest activity of 99.55% in decolorizing of RhB under UV light within 120 min. Ó 2017 Elsevier B.V. All rights reserved.
1. Introduction The degradation of organic contaminants in waste water by photocatalysts has been extensively studied [1]. There are many parameters that can play the role in the properties of photocatalysts: size/nanosize [2–4], energy gap [5], morphology [3] and crystalline degree. One of several photocatalysts, silver (ortho) phosphate (Ag3PO4) is now very interesting for researchers. It has high efficiency over 380–780 nm visible range of the solar spectrum [6]. It is an active semiconductor in photo-oxidation, high activity with absorbance in the visible light and high charged carrier mobility. It has the lowest delocalized charge distribution in conduction band, low electron effective mass and benefit of surface carrier mobility [6,7]. The Ag3PO4 novel semiconductor has quantum efficiency of 90% [6–8] at a wavelength longer than 420 nm [6,8] and has demonstrated the excellent photocatalytic ability for oxidation of water and degradation of organic contaminants in aqueous solution under visible radiation [2,9]. Accordingly, the materials can be synthesized by different methods: hydrothermal [1], ion-exchange [2,5,7] and thermolysis [3,4,10]. In this research, ⇑ Corresponding authors. E-mail addresses: [email protected] (T. Thongtem).
[email protected] (N. Ekthammathat), (A. Phuruangrat), [email protected]
http://dx.doi.org/10.1016/j.matlet.2017.04.131 0167-577X/Ó 2017 Elsevier B.V. All rights reserved.
Ag3PO4 synthesized by precipitation and hydrothermal methods using different synthetic conditions was discussed and the photocatalytic properties were evaluated through the degradation of Rhodamine B (RhB) organic dye molecules.
2. Experiment All reagents were analytical grade and used without further purification. 0.003 mol Na3PO4 and 0.003 mol AgNO3 were separately dissolved in 40 ml DI water each to form two precursor solutions, which were mixed together. The mixed solution was adjusted the pH to 8 by HNO3, stirred at room temperature for 15 min, and hydrothermally processed at 100, 150 and 200 °C for 24 h. Concurrently, the mixed solution was stirred at room temperature (RT ca 32 °C) for 3 h. In the end, the as-synthesized precipitates by hydrothermal and precipitation reactions were separated by filtration, washed with DI water and ethanol, and dried at 70 °C for 24 h for further characterization. Phase and crystalline degree were characterized by an X-ray diffractometer (XRD, Philips X’Pert MPD) using a Cu Ka radiation at 45 kV and 35 mA in the range of 20–75°. The functional/compositional groups of the products diluted with KBr for 40 times were analyzed by a Fourier transform infrared spectrometer (FTIR, Perkin Elmer RX spectrophotometer) over 400–4000 cm–1 range with
S. Krungchanuchat et al. / Materials Letters 201 (2017) 58–61
4 cm–1 resolution. The morphologies were investigated by a field emission scanning electron microscope (FE-SEM, JEOL JSM6335F) operating at 35 kV. Photocatalytic activity of the as-synthesized Ag3PO4 was evaluated through the degradation of RhB in an aqueous solution under UV radiation. 0.15 g photocatalyst was dispersed in 150 ml of 10–5 M RhB aqueous solution, which were stirred in the dark for 30 min to establish an adsorption-desorption equilibrium of RhB on the surface of photocatalyst. Then the light was turned on to initiate photocatalysis. The 5 ml solution was sampled every 20 min and analyzed by a UV-visible spectrometer (Perkin Elmer Lambda
59
25). Photocatalysis was proceeding in a photo-reactor equipped with three 15 W UV germicidal irradiation lamps. Decolorization efficiency (%) was calculated by [(C0 C)/C0] 100, where C0 is the initial concentration of RhB and C is the concentration of RhB after light irradiation. 3. Results and discussion The XRD patterns (Fig. 1a) indicated the phase and crystalline degree of different products corresponding to cubic silver phosphate (Ag3PO4) with lattice parameter of 6.0130 Å and P43n space
Fig. 1. (a) XRD patterns and (b) FTIR spectra of Ag3PO4 synthesized in the solutions with the pH of 8 by precipitation at RT for 3 h and by hydrothermal method at 100, 150 and 200 °C for 24 h.
Fig. 2. SEM images of Ag3PO4 synthesized in the solutions with the pH of 8 by (a) precipitation at RT for 3 h and (b–d) hydrothermal method at 100, 150 and 200 °C for 24 h, respectively.
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group (JCPDS No. 06-0505) [11]. The average crystal size calculated by Scherrer formula [12] was 154–166 nm. The intensities of all XRD peaks were increased with the increase of reaction temperature from RT to 150 °C, and remained unchanged at 200 °C. The crystalline degree was not significantly increased although the synthetic temperature was higher than 150 °C. Thus, the highest crystalline degree was obtained at 150 °C. In this research, the solid material was separated from a liquid only in basic solution, and Ag3PO4 precipitated as pure product in the solution with the pH of 8. Fig. 1b shows the FTIR spectra of Ag3PO4 synthesized at RT, 100 °C and 150 °C over the range of 400–4000 cm–1. Strong bands centered at 555 cm–1 were assigned as the O@PAO bending vibration and at 1010 cm–1 as the asymmetric stretching of (PO4)3 groups [12]. The 1650 cm–1 band is due to H2O bending mode. The absorption band at 3400–3650 cm–1 is related to the stretching vibration of adsorbed water [2,13,14]. The products synthesized at different conditions were characterized by SEM (Fig. 2). At RT precipitation for 3 h, Ag3PO4 was composed of a number of nanoparticles with 100–200 nm in diameter. They were clustered together in groups with different orientations. For the hydrothermal reaction at 100 °C for 24 h, the size of the product was increased and remained as clusters with 250– 1000 nm diameter. At 150 and 200 °C, the Ag3PO4 products shape like dodecahedrons (a solid figure with twelve flat sides) with the size of 1.5–2 mm and 2–4 mm, respectively. The degradation of RhB as a model organic contaminant at a major absorption band of 553 nm (Fig. 3) shows evolution of the
spectral intensities during the photodegradation of RhB by Ag3PO4 particles synthesized at different conditions under UV radiation. The absorption intensity gradually decreased and the solutions were decolorized from pink into colorless within 120 min. The degradation of RhB by different products has different rates (Fig. 4). Comparing to the blank, the RhB degradation by the assynthesized Ag3PO4 products within 120 min was 98.66, 99.23, 99.55 and 84.23% for the products synthesized at RT, 100 °C, 150 °C and 200 °C, respectively. Photodegradation of the 200 °C product is the lowest. Possibly, the particles are too large to be used for photocatalysis. In this research, Ag3PO4 dodecahedrallike particles synthesized at 150 °C for 24 h is the best promising photocatalyst for photodegradation of RhB. It can degrade RhB very quickly within 120 min by transforming the pink solution into a colorless one. A proposed mechanism can be explained by the production of H2O2 and OH during the photocatalysis. Photogeneration of H2O2 was proceeding throughout the process. Its concentration was increased with increasing in the irradiation time, suggesting that two-electron reduction of dissolved oxygen took place on the Ag3PO4 surface [9]. The reduction potential at the CB level of Ag3PO4 is +0.45 V (vs NHE) [5,9]. Direct electron transfer to oxygen molecules (O2 + e ? O2 ) requires 0.284 V (vs NHE) [5,9] and formation of HO2 (O2 + H+ + e ? HO2 requires 0.046 V) was very difficult. The accumulated electrons in the CBAg3PO4 diffused to oxygen species through the multi-electron processes [5]: O2 + 2H+ + 2e ? H2O2 requires +0.682 V and O2 + 4H+ + 4e ? 2H2O requires +1.23 V [9]. They are higher than the CBAg3PO4
Fig. 3. UV-visible absorption of RhB photocatalyzed by Ag3PO4 synthesized in the solutions with the pH of 8 by (a) precipitation at RT for 3 h and (b–d) hydrothermal reactions at 100, 150 and 200 °C for 24 h, respectively.
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at room temperature without any surfactant adding. Ag3PO4 synthesized in the solution with the pH of 8 at 150 °C for 24 h has the highest efficiency (99.55%) in photodegradation of RhB under UV radiation within 120 min. Acknowledgements We wish to thank Chiang Mai University, Thailand for providing financial support through the Center of Excellence in Materials Science; Chiang Mai University (CMU) through the CMU’s 50th Anniversary Ph.D. Grant; and Science and Applied Science Center (SASC), Bansomdejchaopraya Rajabhat University, Thailand through a general support. References
Fig. 4. Decolorization efficiency of RhB photocatalyzed by Ag3PO4 synthesized in the solutions with the pH of 8 by precipitation at RT for 3 h and by hydrothermal reactions at 100, 150 and 200 °C for 24 h comparing with that of the blank.
potential. Furthermore, photogenerated holes tended to remain on the surface of Ag3PO4 due to the large negative charge of PO34 ions which preferred to attract holes and repel electrons. Meanwhile PO34 ions have strong bonding ability with H2O. Thus, H2O could be easily adsorbed on surface and oxidized by the holes to hydroxyl radicals (OH) which eventually degraded the RhB dye to CO2 and H2O [8,15]. 4. Conclusions In summary, Ag3PO4 particles were successfully synthesized by both hydrothermal reaction at high temperature and precipitation
[1] M.Q. Wen, T. Xiong, Z.G. Zhang, W. Wei, X.T. Tang, F. Dong, Opt. Express 24 (2016) 258178. [2] J. Ma, J. Zou, L. Li, C. Yao, T. Zhang, D. Li, Appl. Catal. B 134–135 (2013) 1–6. [3] M. Ramezani, A. Sobhani-Nasab, S.M. Hosseinpour-Mashkani, J. Mat. Sci. Mater. Electron. 26 (2015) 4848–4853. [4] S.M. Hosseinpour-Mashkani, A. Sobhani-Nasab, J. Mat. Sci. Mater. Electron. 28 (2017) 4345–4350. [5] S.B. Rawal, S.D. Sung, W.I. Lee, Catal. Commun. 17 (2012) 131–135. [6] K. Shen, M.A. Gondal, R.G. Siddique, S. Shi, S. Wang, J. Sun, Q. Xu, Chin. J. Catal. 35 (2014) 78–84. [7] X. Yan, Q. Gao, J. Qin, X. Yang, Y. Li, H. Tang, Ceram. Inter. 39 (2013) 9715–9720. [8] Y. Liu, L. Fang, H. Lu, Y. Li, C. Hu, H. Yu, Appl. Catal. B 115–116 (2012) 245–252. [9] H. Katsumata, M. Taniguchi, S. Kaneco, T. Suzuki, Catal. Commun. 34 (2013) 30–34. [10] A. Javidan, M. Ramezani, A. Sobhani-Nasab, S.M. Hosseinpour-Mashkani, J. Mat. Sci. Mater. Electron. 26 (2015) 3813–3818. [11] Powder Diffract. File, JCPDS-ICDD, 12 Campus Bld., Newtown Square, PA 19073–3273, U.S.A., 2001. [12] A. Morato, V. Rives, Appl. Catal. B 202 (2017) 418–419. [13] J. Zhang, H. Bi, G. He, Y. Zhou, H. Chen, J. Environ. Chem. Eng. 2 (2014) 952– 957. [14] A. Wu, C. Tian, W. Chang, Y. Hong, Q. Zhang, Y. Qu, H. Fu, Mater. Res. Bull. 48 (2013) 3043–3048. [15] A. Phuruangrat, P. Dumrongrojthanath, S. Thongtem, T. Thongtem, Mater. Lett. 194 (2017) 114–117.