Effects of Structural and Textural Aspects on the Photocatalytic Performance of Zirconium Hydrogen Phosphate Doped with Tin Metal¹

Abstract—The preparation of zirconium hydrogen phosphate, α-Zr(HPO₄)₂ · H₂O (α-ZrP), and its tin dopped derivatives were described. The structural and textural properties of the prepared materials were examined and their effect on catalytic performance in the removal of dyes such as methyl red and methylene blue from the aqueous solutions was revealed. The crystalline zirconium hydrogen phosphate was prepared by the interaction between zirconium tetrachloride and phosphoric acid in the presence of fluoric acid. The α-ZrP samples doped with tin were obtained by the impregnation method. X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and nitrogen adsorption analysis were applied to explore the structural and textural properties of α-ZrP modified by the addition of various amounts of tin. The obtained results indicated a significant effect of the tin amount on these properties. As a result of tin addition, a gradual decrease in the crystallinity of the samples was observed with the appearance of preferred orientation for the [002] planes. These changes coincided with an increase in the surface area and the total pore volume as well as a decrease in pore diameter. Investigation of the photocatalytic activity of the studied materials in the degradation methyl red and methylene blue indicated a significant increase in the degradation extent of the dyes with increasing amount of tin.