Preparation of porous α-Fe2O3 thin films for efficient photoelectrocatalytic degradation of basic blue 41 dye. Issue 4 (August 2021)

• Record Type: Journal Article
• Authors: Machreki, Manel; Chouki, Takwa; Martelanc, Mitja; Butinar, Lorena; Vodopivec, Branka Mozetič; Emin, Saim
• Is Part Of: Journal of environmental chemical engineering. Volume 9:Issue 4(2021)
• Publication Date: 2021-08
• Subjects: α-Fe2O3 thin films -- Photoelectrocatalysis -- Kinetics -- Visible light -- Degradation -- Textile dye; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2021.105495
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: A novel method was developed for the preparation of porous hematite (α-Fe2 O3 ) thin films. First, a solution containing iron precursor was spin-coated on fluorine-doped tin oxide substrate and later short heat-treated at 750 °C. The prepared α-Fe2 O3 thin films were applied as dual-function catalyst in photoelectrochemical (PEC) water oxidation and textile dye degradation studies. For the first time, α-Fe2 O3 thin films were used in efficient PEC degradation of a textile dye (Basic Blue 41 – B41) using in-situ generated reactive chlorine species. In comparison with photocatalytic and electrocatalytic approaches, the PEC technique allows faster degradation of B41 dye at an applied bias potential of 1.5 V versus reversible hydrogen electrode and under visible light illumination. In the presence of Cl − using the PEC approach the degradation of B41 reaches 99.8%. High-performance liquid chromatography coupled with UV–VIS system confirmed the degradation of B41 dye using PEC. Gas-chromatography coupled to mass spectrometry was used to study the by-products obtained during PEC degradation. Chemical oxygen demand analyses confirmed that the mineralization level of B41 is in the order of 68%. The α-Fe2 O3 films developed in this study give a higher level of PEC degradation efficiency compared to other iron oxide-based systems. Graphical Abstract: ga1 Highlights: Preparation of α-Fe2O3 thin films were achieved using combined spin-coating and short heat treatment approaches. α-Fe2 O3 thin films show good stability against photocorrosion. PEC using α-Fe2O3 thin films present a promising way for degradation of a Basic Blue 41 dye with free chlorine species. HPLC and GC-MS studies confirmed the degradation of Basic Blue 41 dye.