ZnO/bentonite Nanocomposites Prepared with Solid-state Ion Exchange as Photocatalysts

Document Type: Research Paper

Authors

1 Department of Chemical Engineering, University of Mohaghegh Ardabili, Ardabil, Iran.

2 Department of Civil Engineering, University of Mohaghegh Ardabili, Ardabil, Iran.

Abstract

Photocatalyst nanocomposites of ZnO/bentonite clay are synthesized by Solid-state ion exchange method. Ion exchange intercalation process of clays is used to incorporate the catalyst into the basal space of the layered structure of clays. The purpose of this study is to find a new method, which is focused on simplifying and saving time to prepare ZnO-bentonite composite with photocatalyst property. The synthesis of ZnO-doped bentonite nanocomposite is accomplished by placing bentonite in a melting bath of ZnSO4 for 10, 20, 40, 60 and 90 min. The nanocomposites are characterized by morphological (SEM), optical (UV/vis reflection) and analytical (EDX) techniques. According to SEM results, after ion exchanging, the parent structure of bentonite remains and only the distance between flakes increased significantly. EDX analysis clearly suggest the success of ion exchange of the expense of Ca2+, Na+ and Mg2+ cations with Zn2+. The calculated band gap for the composites were 3.14 eV (10 min), 2.64 eV (20 min) and 2.54 eV at longer times, respectively. All the prepared composites showed acceptable degradation performances. The greatest photocatalytic activity is detected in ZnO/bentonite composite solid-state ion exchanges which lasts 60 and 90 min. Leaching test results showed that the concentrations of Zn are less than 4 mg/l between 0 and 6 h. These results indicated that the photocatalytic property of composites would last longer.

Keywords

References

  1. Barbosa, L.V., et al., Kaolinite-titanium oxide nanocomposites prepared via sol-gel as heterogeneous photocatalysts for dyes degradation. Catalysis Today, 2015. 246: p. 133-142.
  2. Meshram, S., et al., Continuous flow photocatalytic reactor using ZnO–bentonite nanocomposite for degradation of phenol. Chemical Engineering Journal, 2011. 172(2-3): p. 1008-1015.
  3. Akkari, M., et al., ZnO/clay nanoarchitectures: Synthesis, characterization and evaluation as photocatalysts. Applied Clay Science, 2016. 131: p. 131-139.
  4. Lee, K.M., et al., Recent developments of zinc oxide based photocatalyst in water treatment technology: A review. Water Research, 2016. 88: p. 428-448.
  5. Bel Hadjltaief, H., et al., Photocatalytic decolorization of cationic and anionic dyes over ZnO nanoparticle immobilized on natural Tunisian clay. Applied Clay Science, 2018. 152: p. 148-157.
  6. Pouraboulghasem, H., et al., Synthesis, characterization and antimicrobial activity of alkaline ion-exchanged ZnO/bentonite nanocomposites. Journal of Central South University, 2016. 23(4): p. 787-792.
  7. Lotfiman, S. and M. Ghorbanpour, Antimicrobial activity of ZnO/silica gel nanocomposites prepared by a simple and fast solid-state method. Surface and Coatings Technology, 2017. 310: p. 129-133.
  8. Gilani, S., M. Ghorbanpour, and A. Parchehbaf Jadid, Antibacterial activity of ZnO films prepared by anodizing. Journal of Nanostructure in Chemistry, 2016. 6(2): p. 183-189.
  9. Fatimah, I., S. Wang, and D. Wulandari, ZnO/montmorillonite for photocatalytic and photochemical degradation of methylene blue. Applied Clay Science, 2011. 53(4): p. 553-560.
  10. Trabelsi, H., et al., Solar Photocatalytic Decolorization and Degradation of Methyl Orange Using Supported TiO2. Journal of Advanced Oxidation Technologies, 2016. 19(1).
  11. Byrappa, K., et al., Impregnation of ZnO onto activated carbon under hydrothermal conditions and its photocatalytic properties. Journal of Materials Science, 2006. 41(5): p. 1355-1362.
  12. Pourabolghasem, H., M. Ghorbanpour, and R. Shayegh, Antibacterial Activity of Copper-doped Montmorillonite Nanocomposites Prepared by Alkaline Ion Exchange Method. Journal of Physical Science, 2016. 27(2): p. 1-12.
  13. Preface: 6th International Biennial Conference on UltraFine Grained and Nanostructured Materials (UFGNSM 2017). 2018, Author(s).
  14. Garshasbi, N., et al., Preparation of Zinc Oxide-Nanoclay Hybrids by Alkaline Ion Exchange Method. Brazilian Journal of Chemical Engineering, 2017. 34(4): p. 1055-1063.
  15. Ghorbanpour, M. and S. Lotfiman, Solid-state immobilisation of titanium dioxide nanoparticles onto nanoclay. Micro & Nano Letters, 2016. 11(11): p. 684-687.
  16. Zhi, Y., et al., ZnO Nanoparticles Immobilized on Flaky Layered Double Hydroxides as Photocatalysts with Enhanced Adsorptivity for Removal of Acid Red G. Langmuir, 2010. 26(19): p. 15546-15553.
  17. Fernández, L., et al., Mesosynthesis of ZnO–SiO2porous nanocomposites with low-defect ZnO nanometric domains. Nanotechnology, 2008. 19(22): p. 225603.
  18. Ghosh, A. and A. Mondal, Fabrication of stable, efficient and recyclable p-CuO/n-ZnO thin film heterojunction for visible light driven photocatalytic degradation of organic dyes. Materials Letters, 2016. 164: p. 221-224.
  19. Ye, J., et al., Photocatalytic degradation of phenol over ZnO nanosheets immobilized on montmorillonite. Materials Science in Semiconductor Processing, 2015. 39: p. 17-22.
  20. Xu, H., T. Yu, and J. Liu, Photo-degradation of Acid Yellow 11 in aqueous on nano-ZnO/Bentonite under ultraviolet and visible light irradiation. Materials Letters, 2014. 117: p. 263-265.
 

Journal of Ultrafine Grained and Nanostructured Materials

Volume 51, Issue 2
December 2018
Pages 139-146

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