Recoverable and reusable visible-light photocatalytic performance of CVD grown atomically thin MoS2 films

• Published in: Chemosphere (Oxford) 2022-01, Vol.287, p.132347-132347, Article 132347
• Main Authors: Sindhu, Abhishek Singh, Shinde, Nitin Babu, Harish, S., Navaneethan, M., Eswaran, Senthil Kumar
• Format: Article
• Language: English
• Subjects: 2D Layers; CVD; Dye-degradation; MoS2; Photocatalysis
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2021.132347

The decomposition of water pollutants including industrial dyes and chemicals via photocatalytic decontamination is one of the major investigated problems in recent years. Two-dimensional molybdenum disulfide (MoS2) layers have shown great promise as an efficient visible-light photocatalyst owing to its numerous active sites and large surface area. In this study, atomically thin MoS2 films of different thicknesses from monolayer to five-layer and ten layers were fabricated on sapphire substrates using chemical vapor deposition (CVD). We demonstrate that these MoS2 thin films can be used as a photocatalyst to degrade Methylene Blue (MB) dye and can be recovered completely with utmost structural and chemical stability. Under visible-light irradiation, the MB absorption peak completely disappears with ∼95.6% of degradation after 120 min. We also demonstrate the reusability of the MoS2 thin films without significantly losing the photocatalytic activity even after 5-cycles of degradation studies. The chemical and structural stability of the MoS2 films after 5-cycles of degradation studies were affirmed using various spectroscopic studies. Our findings suggest that the MB degradation efficiency increases from 19.01% to 98.46% with an increase in pH from 4 to 14. Our approach may facilitate a further design of other transition metal dichalcogenides-based recoverable photocatalysts for industrial applications. [Display omitted] •CVD grown atomically thin MoS2 films show photocatalytic activity towards degradation of M Methylene Blue (MB) dye.•The MoS2 films exhibited a degradation efficiency in the range 94.1–95.5%.•The photocatalytic MoS2 films are easily recoverable and reusable.•The films exhibit high structural and chemical stability even after 5-cycles of the degradation studies.