Cyclic Voltammetry Study and Solar Light Assisted Photocatalytic Activity of the CeFeO3/CeO2/Fe2O3 Composite

Abstract

The semiconducting nature of CeFeO₃/CeO₂/Fe₂O₃ nanocomposite has permitted the degradation of the organic toxic dye methylene blue under the irradiation of ultraviolet and visible light portions of solar radiation. Fullprof-assisted Rietveld refinement analysis, performed using the Match software, has revealed the orthorhombic nature of CeFeO₃. In addition, in the synthesized material, the cubic phase byproduct CeO₂ was found due to the highly oxidizing nature of the cerium element. This occurred due to 6 min microwave irradiation because the microwave-assisted technique offered random distribution of heating during the supply of 800-W power for 30 s, followed by 12 cycles. Additionally, the presence of Fe₂O₃ was also confirmed through Match software-assisted Rietveld refinement analysis through phase matching. During the synthesis, a certain portion of the synthesized CeFeO₃ experienced overheating, leading to phase transformation from CeFeO₃ into Fe₂O₃ and CeO₂. The unit cell compositions of CeFeO₃, CeO₂, and Fe₂O₃ were found in the sample material with 35.54%, 52.43%, and 12.03%, respectively. The appearance of a fingerprint absorption region in the FTIR spectrum around 577.36 and 535.38 cm⁻¹ further confirmed the similarity of these values (577.36 and 535.38 cm⁻¹) to those obtained from the calculated values obtained by substituting Rietveld refined bond length parameters. The fourth step process in the thermal analysis curve (TGA) revealed the oxidation process, which led to the destruction of the CeFeO₃ phase, causing the transformation of CeFeO₃ into two byproducts (CeO₂ and Fe₂O₃). This oxidation process permitted in an observable weight gain, which is observed in the thermal analysis curve (TGA). A cyclic voltammetry study (the experimentally measured current–voltage characteristic curve) revealed slightly distorted semirectangular CV curves, confirming the pseudo-capacitive behavior of the synthesized composite.