Construction of thermo-responsive polymer brushes decorated Fe3O4@catechol-formaldehyde resin core-shell nanospheres stabilized carbon dots/PdNPs nanohybrid and its application as an efficient catalyst
In recent years, there has been growing interest in the catalytic properties of noble metal nanoparticles (NMNs) with high surface area and activity. However, the instability and easy self-aggregation of NMNs limit their broad application in catalysis. The integration of polymer into the catalyst system is advantageous for improving the surface properties of catalyst support and stability of NMNs, which is expected to solve the above problem. Herein, we successfully constructed the well-dispersed carbon dots (CDs) decorated Pd nanoparticles supported by thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) brushes functionalized mussel-inspired Fe3O4@catechol formaldehyde resin (CFR) core-shell magnetic nanospheres. Different molecular weights of sulfhydryl-terminated PNIPAM polymers grafted onto the Fe3O4@CFR nanospheres can affect the morphology and catalytic activity of the designed Fe3O4@CFR-S-PNIPAM@Pd/CDs nanohybrids. The as-prepared nanohybrids as catalysts exhibited high catalytic reduction activity because of the synergistic effect of different components with easy separation and recycling stability. The magnetically Pd-based nanocatalyst revealed excellent catalytic efficiency for the Knoevenagel condensation and Suzuki cross-coupling reaction. Additionally, the PNIPAM functionalized nanocatalyst also showed interesting temperature-responsive behavior in the catalytic process. This work has a guiding significance for the design and fabrication of functional nanohybrid materials with controllable structure and chemical composition for industrial catalysis.