Polymer brush-assisted preparation of magnetic Au nanocatalyst for highly efficient reduction of organic pollutants

In this work, magnetic nanoparticles (Fe3O4) immobilized with poly(4-vinylpyridine) (P4VP) brushes were prepared by Cu(0)-reversible deactivation radical polymerization (Cu(0)-RDRP) for the coordination of Au3+, which subsequently yielded Au nanoparticles by Fe3O4 and ethanol reduction system to realize a green synthesis without using toxic chemicals. Morphology observation shows that Fe3O4 @P4VP-Au nanocatalyst is distributed uniformly without significant agglomeration. Au nanoparticles with an average diameter of 2.71 nm are firmly anchored on the surface of Fe3O4 @P4VP-Au by using P4VP brushes as a skeleton to support. The hybrid Fe3O4 @P4VP-Au nanocatalyst demonstrates superior properties such as high structure stability, small size and uniform Au nanoparticles distribution, convenient reuse recovery, and good biocompatibility. It also has remarkable catalytic activity for nitrophenols and methylene blue. The catalytic activity can still keep above 98.5% even after ten cycles. This study presents a green and simple route for Au-nanocatalyst synthesis, which provides fresh insights and useful implications for designing efficient and sustainable Au nanocatalysts.