Photodegradation of Azo Dyes in Sunlight Promoted by Nitrogen-Sulfur-Phosphorus Codoped Carbon Dots
Journal article, 2021

Removal of organic contaminants such as azo dyes is highly desirable because of their toxicity, stability, and mutagenic properties. Herein an efficient method for the photodegradation of two well-known model azo dyes, namely metanil yellow (MY) and methyl orange (MO), under sunlight by multiple-heteroatom-doped carbon dots (CD) (nitrogen-, sulfur-, and phosphorus-doped-CD (NSP-CD)) is presented. The photodegradation results favored sunlight as a sustainable light source, as its value of t1/2 is significantly less than that of artificial light (100 W tungsten bulb). Various parameters, such as the concentrations of individual dyes (20-100 ppm), a mixture of both dyes, changes in pH, and foreign/interfering ions, were investigated to understand the photocatalytic activity of NSP-CD. Under sunlight, photodegradation of ∼20 ppm of dye was observed in ∼60 min (for MY) and ∼90 min (for MO), respectively. A comparative NMR investigation was performed to confirm the photodegradation of the complex structural framework of azo dyes by NSP-CD. Moreover, to explore the real-life utility of the process, sunlight-promoted photodegradation experiments were conducted by externally spiking four different types of industrial samples. Spiking of MY and MO dyes with concentrations in the range of ∼15-23 ppm showed similar results of photodegradation.

NSP-CD

doping

artificial light

azo dye

photocatalysis

sunlight

pollutant dye

Author

Deepika Saini

Malaviya National Institute of Technology Jaipur

Ruchi Aggarwal

Malaviya National Institute of Technology Jaipur

Amit Kumar Sonker

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Sumit Kumar Sonkar

Malaviya National Institute of Technology Jaipur

ACS Applied Nano Materials

25740970 (eISSN)

Vol. 4 9 9303-9312

Subject Categories

Physical Chemistry

Other Chemistry Topics

Environmental Sciences

DOI

10.1021/acsanm.1c01810

More information

Latest update

4/5/2022 5