Novel RGO-ZnWO4-Fe3O4 nanocomposite as an efficient catalyst for rapid reduction of 4-nitrophenol to 4-aminophenol

Abstract

We report herein a simple, economic, and facile approach for the synthesis of a novel reduced graphene oxide-zinc tungstate-iron oxide (RGO-ZnWO<inf>4</inf>-Fe<inf>3</inf>O<inf>4</inf>) nanocomposite by a one-pot microwave method and its efficiency as a catalyst in reducing 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) using sodium borohydride (NaBH<inf>4</inf>). The as-prepared RGO-ZnWO<inf>4</inf>-Fe<inf>3</inf>O<inf>4</inf> nanocomposites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transformed infrared spectroscopy (FTIR), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) techniques. The prepared nanocomposites showed excellent catalytic performance in the reduction of 4-NP to 4-AP. The reaction was completed in just 40 s at room temperature. The RGO in RGO-ZnWO<inf>4</inf>-Fe<inf>3</inf>O<inf>4</inf> nanocomposite plays an essential role to improve the catalytic performance through facilitation of easy electron transfer and high adsorption of the substrate on graphene sheets. The synergistic effects of RGO, ZnWO<inf>4</inf>, and Fe<inf>3</inf>O<inf>4</inf> in the RGO-ZnWO<inf>4</inf>-Fe<inf>3</inf>O<inf>4</inf> nanocomposite toward reduction, apart from its excellent stability and reusability, make it an efficient candidate as catalyst for hydrogenation reactions of aromatic compounds in research and industrial applications. © 2016 American Chemical Society.