Photocatalytic degradation of methylene blue by nanostructured Fe/FeS powder under visible light

• Published in: International journal of minerals, metallurgy and materials Vol. 25; no. 2; pp. 244 - 252
• Main Authors: Esmaili, Hassan, Kotobi, Amir, Sheibani, Saeed, Rashchi, Fereshteh
• Format: Journal Article
• Language: English
• Published: Beijing University of Science and Technology Beijing 01.02.2018; Springer Nature B.V; School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran 11155-4563, Iran
• Subjects: Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Corrosion and Coatings; Diffuse reflectance spectroscopy; Dosage; Glass; Iron sulfides; Irradiation; Magnetic measurement; Magnetic properties; Materials Science; Metallic Materials; Methylene blue; Nanostructure; Natural Materials; Photocatalysis; Photocatalysts; Photodegradation; Spectrum analysis; Surfaces and Interfaces; Thin Films; Tribology; Ultraviolet reflection; Ultraviolet spectroscopy; X-ray diffraction; 蓝色;光催化剂;粉末;电子显微镜;nano;紫外可见;反应控制;光谱学; methylene blue; iron sulfide; visible light; nanoparticles; photocatalytic degradation; kinetics
• ISSN: 1674-4799; 1869-103X
• DOI: 10.1007/s12613-018-1567-x

The photocatalytic performance of mechano-thermally synthesized Fe/FeS nanostructures formed from micron-sized starting materials was compared with that of a thermally synthesized nanostructure with nano-sized precursors in this paper. The properties of as-synthesized materials were studied by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, vibrating sample magnetometry（VSM）, diffuse reflectance spectroscopy（DRS）, and ultraviolet–visible（UV-Vis） spectroscopy. The effects of irradiation time, methylene blue（MB） concentration, catalyst dosage, and p H value upon the degradation of MB were studied. Magnetic properties of the samples showed that both as-synthesized Fe/FeS photocatalysts are magnetically recoverable, eliminating the need for conventional filtration steps. Degradation of 5 ppm of the MB solution by mechano-thermally synthesized Fe/FeS with a photocatalyst dosage of 1 kg/m~3 at pH 11 can reach 96% after 12 ks irradiation under visible light. The photocatalytic efficiency is higher in alkaline solution. The kinetics of photocatalytic degradation in both samples is controlled by a first-order reaction. However, the rate-constant value in the thermally synthesized Fe/FeS photocatalyst sample is only 1.5 times greater than that of the mechano-thermally synthesized one.