In situ recyclable gold nanoparticles using CO2-switchable polymers for catalytic reduction of 4-nitrophenol

Abstract

CO₂-switchable gold nanoparticles (AuNPs) were prepared by functionalizing AuNPs with CO₂-switchable polymers. Their dispersion–re-dispersion in and separation from aqueous solution can be easily and reproducibly adjusted by CO₂ bubbling through and removal from the solution, enabling unique CO₂ controllable, efficient in situ recycling of NPs. As compared to non-functionalized AuNPs, they exhibit higher catalytic activity (except for the 1st round), easier separation and better reusability for 4-nitrophenol reduction.