Rapid dehalogenation of pesticides and organics at the interface of reduced graphene oxide-silver nanocomposite

Dibyashree Koushik; Soujit Sen Gupta; Shihabudheen M Maliyekkal; T Pradeep

doi:10.1016/j.jhazmat.2016.01.004

Rapid dehalogenation of pesticides and organics at the interface of reduced graphene oxide-silver nanocomposite

J Hazard Mater. 2016 May 5:308:192-8. doi: 10.1016/j.jhazmat.2016.01.004. Epub 2016 Jan 11.

Authors

Dibyashree Koushik¹, Soujit Sen Gupta¹, Shihabudheen M Maliyekkal², T Pradeep³

Affiliations

¹ DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India.
² Environmental Engineering Division, School of Mechanical and Building Sciences, VIT University, Chennai Campus, Chennai, 600127, India.
³ DST Unit of Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India. Electronic address: pradeep@iitm.ac.in.

PMID: 26835896
DOI: 10.1016/j.jhazmat.2016.01.004

Abstract

This paper reports dehalogenation of various organohalides, especially aliphatic halocarbons and pesticides at reduced graphene oxide-silver nanocomposite (RGO@Ag). Several pesticides as well as chlorinated and fluorinated alkyl halides were chosen for this purpose. The composite and the products of degradation were characterized thoroughly by means of various microscopic and spectroscopic techniques. A sequential two-step mechanism involving dehalogenation of the target pollutants by silver nanoparticles followed by adsorption of the degraded compounds onto RGO was revealed. The composite showed unusual adsorption capacity, as high as 1534 mg/g, which facilitated the complete removal of the pollutants. Irrespective of the pollutants tested, a pseudo-second-order rate equation best described the adsorption kinetics. The affinity of the composite manifested chemical differences. The high adsorption capacity and re-usability makes the composite an excellent substrate for purification of water.

Keywords: Adsorption; Degradation; Pesticide; Reduced graphene oxide–silver nanocomposite (RGO@Ag); Water purification.

Publication types

Research Support, Non-U.S. Gov't