Size-Selective Synthesis and Catalytic Application of Polyelectrolyte Encapsulated Gold Nanoparticles Using Microwave Irradiation

Size-controlled gold (Au) nanoparticles (NPs) were synthesized for the first time in large quantities in the presence of poly(N-vinyl-2-pyrrolidone) (PVP) Under microwave heating for just 60 s in aqueous solutions. Results showed that the Au NPs were small in size, which could be successfully controlled through varying the PVP to Au(III) molar ratio and by using different molecular weight PVP molecules. The particles were stable for more than three months in ambient conditions, The synthesized PVP-Au NPs exhibited excellent catalytic activity for the reduction of aromatic nitro compounds by NaBH4 in water. The Au NPs helped in the electron transfer process between the BH4- and nitro compounds, which were successfully reduced to their amino derivatives. The present method is beneficial for fast synthesis of Au NPs as well as reduction of different aromatic nitro compounds.