Fe3O4/PANI/m-SiO2 as robust reactive catalyst supports for noble metal nanoparticles with improved stability and recyclability

Abstract

The development of catalysts with improved stability and efficiency is increasingly important for both economic and environmental reasons. Herein, Fe₃O₄/PANI/m-SiO₂ hybrid core/shell spheres have been successfully synthesized as novel and robust reactive catalyst supports to produce highly stable and recyclable noble metal nanocatalysts. Specifically, Fe₃O₄/PANI/m-SiO₂ hybrid core/shell spheres were firstly fabricated, followed by the addition of noble metal ions to initiate the redox reaction between PANI and noble metal ions to yield noble metal nanoparticles on PANI surfaces. The Fe₃O₄ core and mesoporous SiO₂ shell of the Fe₃O₄/PANI/m-SiO₂ hybrid supports can significantly improve the recycling efficiency and greatly reinforce the stability of catalyst nanoparticles against coagulation, respectively. Various parameters, such as the thickness of the PANI coating and the etching time of the SiO₂ dense shell, were considered in optimizing the catalyst supports. Furthermore, the high stability and recyclability of Fe₃O₄/PANI/Au/m-SiO₂ hybrid catalysts involved in liquid phase reactions were established, implying their potential applications in the field of catalysis.