One-pot synthesis of an Au/Au2S viologen hybrid nanocomposite for efficient catalytic applications

Abstract

We report a facile one-pot synthesis of Au/Au₂S multicomponent nanoparticles supported on viologen (V) as a hybrid nanocomposite. Sodium dithionite was used as the reducing agent for both Au and V precursors and SDS as the stabilizing agent for Au nanoparticles in aqueous reaction medium. Spectroscopy, microscopy and electrochemical measurements confirm the successful composite formation. The as-prepared flower-like composite showed excellent catalytic properties towards the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP). The catalytic activity factor of the Au/Au₂S–V hybrid was highest in comparison to those reported for polymer supported Au nanoparticle catalysts. The enhanced catalytic performance can be attributed to the strong adsorption of 4-NP molecules onto the cationic V matrix and Au₂S nanoparticle surface along with effective donor–acceptor interactions between Au–Au₂S nanoparticles and V facilitating the electron transfer at the hybrid interface.