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  • Original Paper: Sol-gel and hybrid materials for catalytic, photoelectrochemical and sensor applications
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Acid-etched coal fly ash/TiO2 nanocomposites with high photocatalytic degradation efficiency: a high value-added application of coal fly ash


Coal fly ash (CFA), as a kind of aluminosilicate-rich solid wastes that was generated by the combustion of coal, was used as support to load TiO2 nanoparticles to improve the photocatalytic degradation efficiency of textile dye with the advantage of low cost. In this article, a novel acid-etched coal fly ash/TiO2 nanocomposites photocatalyst was prepared by HCl etching followed by sol-gel method. The prepared nanocomposite was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier Transform infrared spectroscopy (FTIR), X-ray photoelectron spectra (XPS) and UV–vis diffused reflectance spectroscopy (DRS) techniques. The photocatalytic degradation efficiency were evaluated by using methyl orange as model. Compared with the CFA (no HCl etching)/TiO2 nanocomposites, the prepared CFA/TiO2 nanocomposites had much better photodegradation efficiency. The preparation and application of CFA/TiO2 nanocomposites will promote the high value-added application of CFA greatly.

Graphical abstract


  • In this article, coal fly ash (CFA) was used as carrier to load TiO2 nanoparticles to improve the photocatalytic degradation efficiency.

  • The improved photocatalytic degradation efficiency was caused by the evenly distributed and unagglomerated TiO2 on the surfaces of coal fly ash as well as the rough surfaces of the modified CFA, which can scatter the irradiated ultraviolet many times.

  • The preparation and application of CFA/TiO2 nanocomposites promote the high value-added application of CFA greatly and eliminate the pollution caused by CFA.

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This work was supported by Natural Science Foundation of Liaoning Province (No. 2021-MS-260).

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Correspondence to Yu Liang.

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Liang, Y., Chen, S., Zhong, J. et al. Acid-etched coal fly ash/TiO2 nanocomposites with high photocatalytic degradation efficiency: a high value-added application of coal fly ash. J Sol-Gel Sci Technol 103, 185–194 (2022).

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  • Coal fly ash
  • HCl etching
  • TiO2
  • Photocatalyst
  • Water-remediation
  • Methyl-orange
  • High value-added application