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Rapid sunlight-driven mineralisation of dyes and fungicide in water by novel sulphur-doped graphene oxide/Ag3VO4 nanocomposite

  • Ragam N. Priyanka
  • Subi Joseph
  • Thomas Abraham
  • Neena J. Plathanam
  • Beena MathewEmail author
Research Article
  • 17 Downloads

Abstract

A semiconductor photocatalyst was prepared in facile, standard conditions by integrating 1% metal-free, sulphur-doped graphene oxide (sGO) as cocatalyst and Ag3VO4 as photocatalyst and characterised via spectroscopic, microscopic and voltammetric techniques. The catalytic activity was performed on notable water pollutants like textile dyes and fungicide employing various techniques. Cationic dyes such as methylene blue and rhodamine B were degraded > 99% with above 90% organic carbon content removal indicating total mineralisation while anionic dyes were degraded 75–80% in 1 h. For the first time, a dithiocarbamate fungicide thiram is degraded to give thiourea as a product in 1 h. Photocatalysis follows pseudo-first order kinetics with rate 3.67, 49.50 and 3.19 times higher than Ag3VO4, sGO and GO-Ag3VO4 respectively with excellent stability and recyclability. One percent sGO aided excellent carrier separation boosted by electrons and surface defects from sGO, morphology and n-n heterojunction formation. The catalyst efficiently removed 82.8% of the total organic carbon content of a real water sample from the textile mill under 2-h sunlight irradiation.

Keywords

Photocatalysis Metal-free cocatalyst Carrier separation n-n Heterojunction Pollutant treatment Textile industry effluent treatment 

Notes

Acknowledgements

Ragam N. Priyanka is grateful to Kerala State Council for Science Technology and Environment (KSCSTE), Kerala, India, for Research Fellowship.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Supplementary material

11356_2019_7569_MOESM1_ESM.docx (2.4 mb)
ESM 1 (DOCX 2468 kb)

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© Springer-Verlag GmbH Germany, part of Springer Nature 2020

Authors and Affiliations

  1. 1.School of Chemical SciencesMahatma Gandhi UniversityKottayamIndia

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