Efficient photocatalytic desulfurization of thiophene under visible light irradiation over flower-like AgBiS2 photocatalyst

Document Type: Original Research Paper

Authors

1 New Technology Faculty, Semnan University, Semnan, Iran.

2 bPolymer Chemistry Department, School of Science, Tehran University, Tehran, Iran

3 cDepartment of Chemistry, Iran University of Science and Technology, Tehran, P.O. Box. 16846-13114, I.R. Iran

10.22034/jna.2020.1895210.1195

Abstract

Here, we report the production of hierarchical flower-like AgBiS2 nanostructures by an amino acid-modified polyol route. This work indicates that by changing the polyol process conditions including kind of capping agent, reaction time and reflux temperature, the sheet-like, cone-like, sphere-like and flower-like morphologies of AgBiS2 micro/nanostructures can be prepared. The phase, elemental composition, morphology and optical characteristics of as-prepared AgBiS2 nanostructures were analyzed by UV–Vis, FESEM, XRD, and EDS techniques. After characterization of the products, the AgBiS2 nanostructures were employed as novel photocatalysts for oxidative desulfurization of thiophene/n-octane solution as model fuel under visible light illumination. Results demonstrate that hierarchical flower-like AgBiS2 photocatalyst with desirable band gap energy (2.44 eV) has high photocatalytic desulfurization performance of about 89% after 2 h of visible light irradiation. As well as, the effects of morphology, photocatalyst dosage and reusability of the AgBiS2 nanostructures on the photocatalytic performance were evaluated. The excellent photocatalytic activity of AgBiS2 photocatalyst can be attributed to the strong visible light absorption, high separation rate of electron–hole pairs, special hierarchical structures and suitable band gap energy. Moreover, a reliable photo-oxidation desulfurization mechanism was discussed according to the active species trapping experiments, which revealed the photo-generated h+ and •O2− radicals were the main active species in the photocatalytic desulfurization process.

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