Preparation of the Ag/RGO nanocomposite by use of Abutilon hirtum leaf extract: A recoverable catalyst for the reduction of organic dyes in aqueous medium at room temperature

Abstract

This paper reports on the biosynthesis, characterization and catalytic activity of silver (Ag) nanoparticles (NPs) supported on the reduced graphene oxide (Ag/RGO) surface using Abutilon hirtum leaf extract as a reducing and capping agent without using any synthetic reagent or toxic chemicals. Introducing A. hirtum leaf extract into an aqueous mixture of AgNO3 and GO caused the speedy reduction of the GO and silver ions and efficiently lead to their nucleation as highly stable Ag NPs on the RGO surface. The crystalline nature of the Ag/RGO nanocomposite was identified using XRD analysis. The possible mechanism leading to the formation of NPs was developed to illustrate this process. The Ag/RGO nanocomposite was employed as catalyst for the reduction of organic dyes such as 4-nitrophenol (4-NP), Congo red (CR) and Rhodamine B (RhB) in the shortest possible time in water at mild conditions. The catalytic reduction reactions were monitored by employing UV-Vis spectroscopy. Furthermore, the nanocomposite can be recovered and recycled several times without significant loss of activity.