Sono-electrodeposition of novel bismuth sulfide films on the stainless steel mesh: Photocatalytic reduction of Cr (VI)

• Published in: Journal of hazardous materials 2020-02, Vol.384, p.121300-121300, Article 121300
• Main Authors: Zargazi, Mahboobeh, Entezari, Mohammad H.
• Format: Article
• Language: English
• Subjects: Bi2S3 film; Cr (VI); Photocatalytic reduction; Pulse mode; Sono-electrodeposition
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2019.121300

[Display omitted] •Bi2S3 thin film synthesized via PS-PED as a simple, one-step and repeatable approach for the first time.•Pumice and fractal structures of Bi2S3 films obtained on the substrate.•Stainless steel mesh used as a suitable substrate with proper characters.•The synthesized films applied for photocatalytic reduction of Cr (VI).•Response surface methodology used for optimization of film procedure with high reduction efficiency. In this work, for the first time, bismuth sulfide (Bi2S3) film formed on the stainless steel mesh surface as a suitable substrate. Different films were synthesized by various combinations of the two methods (sonochemistry and electrochemistry) in continuous and pulse modes. The Bi2S3 films characterized by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and Atomic Force Microscope (AFM). To reach the best film for photocatalytic reduction of Cr (VI), different films were deposited on the substrate by changing three independent variables including pulse times (ton, toff) and sonication amplitude. Response Surface Methodology (RSM) applied for optimization of independent variables by using Central Composite Design (CCD). Here, the films prepared by sono-electrodeposition in pulse modes led to high photocatalytic efficiency in comparison with other films. The results confirmed that ultrasound affected the morphology of film due to the production of cavitation, micro jets and acoustic streaming. On the other hand, ultrasound decreased double layer thickness and dissolved diffusion problems. Sono-electrodeposition in pulse modes produced films with pumice and fractal like structures. The high photocatalytic activity attributed to special morphologies that have key roles in separation of hole/electron pairs and light multi-scattering.