Influence of pH on the structural, spectral, optical, morphological and photocatalytic properties of ZrO2 nanoparticles synthesized by sol–gel technique

• Published in: Journal of materials science. Materials in electronics Vol. 31; no. 18; pp. 15718 - 15730
• Main Authors: Dharr, Ashwati, Arjun, A., Raguram, T., Rajni, K. S.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.09.2020; Springer Nature B.V
• Subjects: Alizarin; Characterization and Evaluation of Materials; Chemistry and Materials Science; Crystal structure; Crystallites; Doppler effect; Energy gap; Fluorescence; Materials Science; Morphology; Nanoparticles; Optical and Electronic Materials; Optical properties; Photocatalysis; Red shift; Sol-gel processes; Synthesis; Zirconium dioxide
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-020-04134-8

In the present work, ZrO 2 nanoparticles are synthesized with different pH (3 to 8) by the sol–gel technique. From X-ray diffraction analysis, the synthesized particles show a tetragonal crystal structure, and the average crystallite size is found to vary from 7.35 to 4.7 nm as the pH increases from 3 to 8. From the FTIR analysis, the peak observed at 621 cm −1 is ascribed to Zr–O vibrations in the nano-tetragonal ZrO 2 . The bandgap values are found to increase from 2.0 to 2.9 eV with an increase in pH. From the PL analysis, the observed peaks show a large band and considerable red shift in the band maximum compared to the bandgap of bulk ZrO 2 . This strongly expresses that the fluorescence involves extrinsic states. From the morphological analysis, the synthesized nanoparticles are found to be spherical in shape and EDS results confirm the presence of Zr and O. The photocatalytic analysis carried out using Alizarin yellow dye, shows that the degradation efficiency is 84.04% for ZrO 2 (S3-pH 6). This is attributed to the excess –OH group present on the surface of ZrO 2 .