Photoelectrocatalytic oxidation of Rhodamine B with sprayed <I>α</I>-Fe<SUB>2</SUB>O<SUB>3</SUB> photocatalyst

Abstract

Spray deposited iron oxide thin films have been synthesized using ferric trichloride precursor in ethanolic medium. The effect of deposition temperature onto photochemical, structural, morphological, optical, luminescence and thermal properties has been investigated. Structural analysis confirms -Fe 2 O 3 (hematite) phase with rhombohedral crystal structure. The SEM images of optimized Fe 2 O 3 thin films show needle like structure with varying grain size from 120-250 nm. The observed direct band gap is varying from 2.16 to 2.21 eV with substrate temperature. Room temperature photoluminescence spectra showed three pronounced emission peaks such as, UV near-band-edge emission peak around 380-436 nm, a blue emission around 468 nm, and green emission around 560 nm. The XPS results revealed the presence of Fe 3+ in Fe 2 O 3 photoelectrode. The photocatalytic oxidation of Rhodamine B (RhB) with hematite Fe 2 O 3 thin films under solar illumination is investigated. The first order rate constants of photocatalysis are evaluated as a function of the initial concentration of RhB. The extent of mineralization has been studied by analyzing total organic carbon (TOC) and chemical oxygen demand (COD). The estimated values of COD, TOC are decreases from 82 to 9.6 mg/l and 78.7 to 13.9 mg/l respectively.

A Review of Electrical Assisted Photocatalytic Technologies for the Treatment of Multi-Phase Pollutants

“…For example, the hematite-Fe 2 O 3 has been considered as one of the potential candidates mainly due to its low cost, high chemical stability, and high absorbance. Low E bg value of 2.2 eV allows the application of visible light energy [54,55]. Other potential promising semiconductor is MnO with an even low E bg value of 1.3 eV to be an interesting functional material with low cost, large surface, electrochemical stability [55], and innocuous character [56,57].…”

Recycling Rusty Iron with Natural Zeolite Heulandite to Create a Unique Nanocatalyst for Green Hydrogen Production

“…Fe 2 O 3 shows an absorption band edges up to 580 nm. The wide absorption band of Fe 2 O 3 in the visible region is due to the direct transition (O 2− 2p→Fe 3+ 3d) and the spin-forbidden-excitations (Fe 3+ 3d→3d), which rises the indirect transitions [36][37][38].…”

Nanocomposite Coating of Multilayered Carbon Nanotube–Titania

“…Thin film coatings are normally stable and permit transmittance [21]. Thin films can be synthesized by various processes, including sol-gel methods [22], chemical vapor deposition, sputter coating [33], spin coating, and spray pyrolysis [23][24][25][26][27]. Layer-by-layer (LBL) self-assembly technique is a versatile route in the film preparation, which is capable of depositing a diversity of materials on various substrates with controlled thickness [28,29,30,35].…”