Visible light photodegradation of 2,4-dichlorophenol using nanostructured NaBiS2: Kinetics, cytotoxicity, antimicrobial and electrochemical studies of the photocatalyst

• Published in: Chemosphere (Oxford) Vol. 287; p. 132174
• Main Authors: Kumar, V.G. Dileep, Balaji, K.R., Viswanatha, R., Ambika, G., Roopa, R., Basavaraja, B.M., Chennabasappa, Madhu, Kumar, C.R. Ravi, Chen, Zhong, Bui, Xuan-Thanh, Santosh, M.S.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-01-2022
• Subjects: 2,4-DCP; Kinetics; NaBiS2; Photodegradation; Visible light; Photodegradation; 2,4-DCP; NaBiS2; Visible light; Kinetics
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/j.chemosphere.2021.132174

Removal of the hazardous and endocrine-disrupting 2,4-dichlorophenol (2,4-DCP) from water bodies is crucial to maintain the sanctity of the ecosystem. As a low bandgap material (1.37 eV), NaBiS2 was hydrothermally prepared and used as a potential photocatalyst to degrade 2,4-DCP under visible light irradiation. NaBiS2 appeared to be highly stable and remained structurally undeterred despite thermal variations. With a surface area of 6.69 m2/g, NaBiS2 has enough surface-active sites to adsorb the reactive molecules and exhibit a significant photocatalytic activity. In alkaline pH, the adsorption of 2,4-DCP on NaBiS2 appeared to decrease whereas, the acidic and neutral environments favoured the degradation. An increase in the photocatalyst dosage enhanced the degradation efficiency from 81 to 86 %, because of higher vacant adsorbent sites and the electrostatic attraction between NaBiS2 and 2,4-DCP. The dominant scavengers degraded 2,4-DCP by forming a coordination bond between chlorine's lone pair of electrons and the vacant orbitals of bismuth, following the order hole>OH > singlet oxygen. Being non-toxic to both natural and aquatic systems, NaBiS2 exhibits antifungal properties at higher concentrations. Finally, the electron-rich NaBiS2 is an excellent electrocatalyst that effectively degrades organic pollutants and is a promising material for industrial and environmental applications.
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•Bimetallic sulphide as a new photocatalyst for the removal of 2,4-DCP.•86 % of degradation was achieved using this photocatalyst under visible light irradiation.•Hydroxyl radicals and superoxide radicals are the main radicals involved in the degradation.•Photoluminescence studies were carried out to depict the mechanism.