In situ synthesis of gold nanoparticles on N-doped graphene quantum dots for highly efficient catalytic degradation of nitrophenol

Abstract

In our work, a simple and green method of in situ synthesis of Au nanoparticles (Au NPs) on graphene quantum dots doped with nitrogen (NGQDs) was reported. Construction of the nanocomposite was accomplished through mixing the NGQDs and HAuCl4·4H2O with no additional reductant and surfactant. The as-obtained Au NPs-NGQDs nanocomposite exhibited high catalytic activity in its application in the degradation of p-nitrophenol (4-NP), a pertinacious pollutant occuring in industrial wastewater. Characterization results indicated that Au NPs were well distributed upon the surface of NGQDs and Au NPs-NGQDs nanocomposites were formed. Such Au NPs can provide high catalytic activity due to its naked catalytic surface with no surfactant capping. Turnover frequency (TOF) was used to examine the catalytic efficiency and its value was obtained to be 12 h−1. Furthermore, the as-obtained catalyst exhibited high reusability in the catalytic process of the degradation of 4-NP. This study indicates that such novel nanocomposite is promising for catalytic degradation of 4-NP.