Eur. Phys. J. Plus (2022) 137: 715
https://doi.org/10.1140/epjp/s13360-022-02919-w

Regular Article

Elucidation of photocatalytic degradation mechanism of an organic pollutant based on Gd_2−xTi_2−xFe_xO₇ nanomaterials under simulated visible light

¹ Department of Physics, College of Science, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, 31441, Dammam, Saudi Arabia
² Basic and Applied Scientific Research Center, Imam Abdulrahman Bin Faisal University, P.O. Box 1982, 31441, Dammam, Saudi Arabia

^a nalonizan@iau.edu.sa

Received: 4 December 2021
Accepted: 5 June 2022
Published online: 20 June 2022

Abstract

The contaminants such as dyes in wastewater discharged into the environment are significant consequences for human health and other species. The current study focuses on photocatalytic degradation of methylene blue dye under visible light treatment, using Fe doped Gd₂Ti₂O₇ with (Fe = 0, 1.5, 2, 2.5, and 3 mM) synthesized via hydrothermal treatment. X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (UV–vis DRS), photoluminescence spectroscopy, scanning electron microscopy, and energy dispersive X-rays spectroscopy are used to examine the physiochemical characteristics of all the fabricated materials. In all photocatalysts, XRD patterns exhibit the primary peaks of the Gd₂Ti₂O₇ phase, indicating that Fe ions are efficiently introduced into the Gd₂Ti₂O₇ lattice. After 240 mints of visible light irradiation, dye discoloration and mineralization are around 99%, utilizing the optimized 2.5 mM Fe-doped Gd₂Ti₂FeO₇. The increased photocatalytic activity should be linked to the simultaneous doping of 2.5 mM Fe³⁺ ions in Gd₂Ti₂FeO₇, which results in a significant decrease in band gap value and increased production of oxygen vacancies, which trap electrons and reduce recombination with photogenerated positive holes.