One-pot synthesis of porous Au-nanoparticles@polymer/reduced graphene oxide composite microspheres by γ-ray radiation and their application as a recyclable high-performance catalyst

Abstract

The synthesis of efficient and recyclable noble metal nanocatalysts has always been a hot research area in nanocatalysis. In this work, novel porous sulfonated polystyrene (SPS)/reduced graphene oxide (rGO) composite microspheres loaded with Au nanoparticles (AuNP@SPS/rGO) were synthesized through γ-ray radiation on a simple one-pot system, i.e. an aqueous solution containing cagelike porous SPS microspheres, GO, and HAuCl₄. rGO and AuNPs with a size of about 12 nm were formed in water simultaneously under γ-ray radiation, and in situ loaded on cagelike porous SPS microspheres. The prepared cagelike AuNP@SPS/rGO microspheres showed far better catalytic performance than conventional non-supported AuNP catalysts, which completed the reduction of o-nitroaniline by NaBH₄ within only 15 s. Furthermore, the prepared cagelike AuNP@SPS/rGO microspheres can be easily recycled from the reaction system by centrifugation with no loss of the catalytic activity. This work indicates that porous polymer/rGO composite microspheres can be used as a promising support to prepare recyclable metallic nanocatalysts with ultra-high catalytic activity.