Magnetically Separable Pd(0)-Polymer Brush on Rgo for Efficient Nitrophenols Reduction

Abstract

In this study, a facile and effective method is reported for the fabrication of a polydopamine/polyacrylamide co-deposited on magnetic reduced graphene oxide (PDOPA/PAAm@mag-rGO) composite, which offers a new host material for dispersing palladium nanoparticles (Pd NPs) for catalytic reduction of nitrophenols. PDOPA/PAAm was grafted onto mag-rGO through one-step dopamine-triggered polymerization in a short time (45 min) at room temperature. PDOPA/PAAm@mag-rGO not only was used as support but also supplied compatibility and stabilizing Pd N Ps deposition, which enhanced the catalytic properties. The catalytic efficiency of the Pd-PDOPA/PAAm@mag-rGO was carried out with the reduction of 2-nitrophenol, 4-nitrophenol, and 2,4-dinitrophenol by using NaBH4 as a reducing agent at room temperature. The reduction rate of the aforementioned nitrophenols was as follows: 4-nitrophenol>2-nitrophenol>2,4-dinitrophenol. Moreover, the catalyst showed high stability and catalytic efficiency over five sequential uses in the reduction reaction. Magnetic analysis reveals that the as-prepared catalyst had superparamagnetic properties, which allow the easy recovery of the catalyst from the reaction medium via an external magnet. This study also indicates that polymer brushes and noble metal nanoparticles combined with magnetic reduced graphene oxide can play an efficient composite material for the fabrication of multifunctional and multi-component graphene-based materials for diverse catalytic applications.