English

Construction and Visible-Light-Driven Photocatalytic Properties of LaCoO₃-TiO₂ Nanotube Arrays

• GONG Cheng ^1,2, ,
• XIANG Siwan ^1,2, ,
• ZHANG Zeyang ^1,2, ,
• SUN Lan ^{1,2, ,} ,
• YE Chenqing ^2, ,
• LIN Changjian ^1,

• 1.

  State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, P. R. China

• 2.

  Fujian Provincial Key Laboratory of Featured Materials in Biochemical Industry, Ningde Normal University, Ningde 352100, Fujian Province, P. R. China

Corresponding author: SUN Lan, Email: sunlan@xmu.edu.cn; Tel.: +86-592-2189354

• Received Date: 29 May 2018
  Accepted Date: 17 July 2018
  Revised Date: 16 July 2018
  Available Online: 15 June 2019
• Fund Project:

  The project was supported by the National Natural Science Foundation of China (21621091) and Guangdong Natural Science Foundation, China(2016A030313845)

Abstract: TiO₂ nanotube arrays (NTAs) have high photocatalytic activity; however, their weak visible light absorption limits their solar energy utilization and environmental application. Perovskite (ABO₃)-type oxides with a narrow band gap can absorb visible light in a wide wavelength range and have excellent stability; however, their photocatalytic activity is relatively low. Coupling TiO₂ NTAs with ABO₃ to form heterojunctions is one of the most promising approaches to extend the optical absorption of TiO₂ NTAs into the visible-light range and promote the separation rate of photogenerated electron–hole pairs. However, to date, constructing ABO₃-TiO₂ NTA heterostructured composites has been extremely challenging owing to the different crystallization temperatures of anatase TiO₂ NTAs and ABO₃. In this work, LaCoO₃ nanoparticles were first synthesized using a sol-gel method. The as-prepared LaCoO₃ nanoparticles were then modified on the surface of the TiO₂ NTAs using an electrophoretic deposition technique, and a series of LaCoO₃-TiO₂ NTAs photocatalysts were thus constructed by controlling the deposition time. Results of the scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) demonstrated that the nanoparticles prepared through the sol-gel method were LaCoO₃ with a uniform size and high crystallization. The average diameter of the LaCoO₃ nanoparticles was 100 nm. The binding strength between the LaCoO₃ nanoparticles and the TiO₂ NTAs was strong. The UV-visible absorption spectra (diffuse reflectance spectroscopy; DRS) demonstrated that the absorption band edge of the LaCoO₃-TiO₂ NTAs was gradually red-shifted into the visible light region with the increase in electrophoretic time. The LaCoO₃-TiO₂ NTAs prepared by the electrophoretic deposition technique for 15 min exhibited a strong light absorption in the wide wavelength range from 250 to 700 nm, which was the same as that of the LaCoO₃ nanoparticles loaded on a Ti foil. The results of the photocatalytic degradation of methyl orange (MO) under visible light irradiation demonstrated that the photocatalytic degradation rate of MO over LaCoO₃-TiO₂ NTAs was considerably higher than those of TiO₂ NTAs and LaCoO₃ nanoparticles loaded on a Ti foil. The LaCoO₃-TiO₂ NTAs prepared by the electrophoretic deposition technique for 15 min showed the highest photocatalytic degradation rate of MO, which was a four-fold enhancement compared to that of TiO₂ NTs under the same conditions. The p-n heterojunctions between the LaCoO₃ nanoparticles and the TiO₂ nanotubes were responsible for the enhanced visible light photocatalytic activity. The results of the electrochemical impedance spectroscopy (EIS) and photoluminescence spectroscopy (PL) tests demonstrated that the loading of the LaCoO₃ nanoparticles effectively promoted the separation and transport of photogenerated charges, thereby enhancing the visible light photocatalytic activity of the TiO₂ NTAs.

Key words:
• LaCoO₃
•  /  TiO₂ nanotube arrays
•  /  Visible light
•  /  Photocatalysis
•  /  Methyl orange

• 1. [1]

     Wu, L.; Zhang, M.; Li, J.; Cen, C.; Li, X. Res. Chem. Intermed. 2016, 42, 4569. doi: 10.1007/s11164-015-2297-6

  2. [2]

     Xiao, F. X.; Liu, B. Nanoscale 2017, 9, 17118. doi: 10.1039/c7nr06697j

  3. [3]

     Leung, D. Y.; Fu, X.; Wang, C.; Ni, M.; Leung, M. K.; Wang, X. ChemSusChem. 2010, 3, 681. doi: 10.1002/cssc.201000014

  4. [4]

     Wang, J.; Lin, Z. Chem. Mater. 2010, 22, 579. doi: 10.1021/cm903164k

  5. [5]

     Wang, M.; Ioccozia, J.; Sun, L.; Lin, C.; Lin, Z. Energy Environ. Sci. 2014, 7, 2182. doi: 10.1039/c4ee00147h

  6. [6]

     Zhou, H.; Ge, J.; Zhang, M.; Yuan, S. Res. Chem. Intermed. 2016, 42, 1929. doi: 10.1007/s11164-015-2126-y

  7. [7]

     Xiao, F. X.; Liu, B. Adv. Mater. Interfaces 2018, 5, 1701098. doi: 10.1002/admi.201701098

  8. [8]

     Wu, Z; Gong, C; Yu, J; Sun, L; Xiao, W.; Lin, C. J. Mater. Chem. A 2017, 5, 1292. doi: 10.1039/c6ta07420k

  9. [9]

     Chen, C.; Ye, M.; Lv, M.; Gong, C.; Guo, W.; Lin, C. Electrochim. Acta 2014, 121, 175. doi: 10.1016/j.electacta.2013.12.106

  10. [10]

      Chen, H.; Fu, W.; Yang, H.; Sun, P.; Zhang, Y; Wang, L.; Zhao, W.; Zhou, X.; Zhao, H.; Jing, Q.; Qi, X; Li, Y. Electrochim. Acta 2010, 56, 919. doi: 10.1016/j.electacta.2010.10.003

  11. [11]

      Su, Y.; Wu, Z.; Wu, Y.; Yu, Y.; Sun, L.; Lin, C. J. Mater. Chem. A 2015, 3, 8537. doi: 10.1039/c5ta00839e

  12. [12]

      Sun, L.; Wu, Z.; Xiang, S.; Yu, Y.; Wang, Y.; Lin, C.; Lin, Z. RSC Adv. 2017, 7, 17551. doi: 10.1039/c6ra27388b

  13. [13]

      Britoa, J. F.; Tavella, F.; Genovese, C.; Ampelli, C.; Zanoni, M. V. B.; Centi, G.; Perathoner, S. Appl. Catal. B: Environ. 2018, 224, 136. doi: 10.1016/j.apcatb.2017.09.071

  14. [14]

      Xiao, F. X.; Zhang, J. J. Mater. Chem. A 2017, 5, 23681. doi: 10.1039/c7ta08415c

  15. [15]

      Xie, K.; Wu, Z.; Wang, M.; Yu, J.; Gong, C.; Sun, L.; Lin, C. Electrochem. Commun. 2016, 63, 56. doi: 10.1016/j.elecom.2015.12.013

  16. [16]

      Zeng, Z.; Xiao, F. X.; Phan, H.; Chen, S.; Y, Z.; Wang, R.; Nguyen, T. Q.; Tan, T. T. Y. J. Mater. Chem. A 2018, 6, 1700. doi: 10.1039/c7ta09119b

  17. [17]

      Mao, Z.; Lin, H.; Xu, M.; Miao, J.; He, S.; Li, Q. J. Appl. Electrochem. 2018, 48, 147. doi: 10.1007/s10800-017-1138-2

  18. [18]

      Zhang, W.; Liu, J.; Guo, Z.; Yao, S.; Wang, H. J. Mater. Sci: Mater. Electron. 2017, 28, 9505. doi: 10.1007/s10854-017-6694-z

  19. [19]

      Zhao, Q.; Ren, Y.; Li, X.; Shi, Y. Mater. Res. Bull. 2016, 83, 396. doi: 10.1016/j.materresbull.2016.06.031

  20. [20]

      Xiang, S.; Zhang, Z.; Gong, C.; Wu, Z.; Sun, L.; Ye, C.; Lin, C. Mater Lett. 2018, 216, 1. doi: 10.1016/j.matlet.2017.12.101

  21. [21]

      Grabowska, E. Appl. Catal. B: Environ. 2016, 186, 97. doi: 10.1016/j.apcatb.2015.12.035

  22. [22]

      Meziani, D.; Reziga, A.; Rekhila, G.; Bellal, B.; Trari, M. Energy Convers. Manage. 2014, 82, 244. doi: 10.1016/j.enconman.2014.03.028

  23. [23]

      Guo, J.; Dai, Y.; Chen, X.; Zhou, L.; Liu, T. J. Alloy. Compd. 2017, 696, 226. doi: 10.1016/j.jallcom.2016.11.251

  24. [24]

      Ling, F.; Anthony, O. C.; Xiong, Q.; Luo, M.; Pan, X.; Jia, L.; Huang, J.; Sun, D.; Li, Q. Int. J. Hydrogen Energy 2016, 41, 6115. doi: 10.1016/j.ijhydene.2015.10.036

  25. [25]

      Qin, J.; Lin, L.; Wang, X. Chem. Commun. 2018, 54, 2272. doi: 10.1039/c7cc07954k

  26. [26]

      Niu, K.; Liang, L.; Li, J.; Zhang, F. Micropor. Mesopor. Mat. 2016, 220, 220. doi: 10.1016/j.micromeso.2015.09.007

  27. [27]

      Hu, M.; Zhang, Q.; Gu, L.; Guo, Q.; Cao, Y.; Kareev, M.; Chakhalian, J.; Guo, J. Appl. Phys. Lett. 2018, 112, 031603. doi: 10.1063/1.5006298

  28. [28]

      Xie, K.; Gong, C.; Wang, M.; Sun, L.; Lin, C. J. Appl. Electrochem. 2017, 47, 959. doi: 10.1007/s10800-017-1093-y

  29. [29]

      Wu, Z.; Wang, Y.; Sun, L.; Mao, Y.; Wang, M.; Lin. C. J. Mater. Chem. A 2014, 2, 8223. doi: 10.1039/c4ta00850b

•