Production of Au/phosphonium polymer nanoparticles

The introduction of cationic groups onto the surface of gold nanoparticles (GNPs) is a valuable synthetic technique with many applications. This study reports the synthesis of the functionalization of GNPs with phosphonium groups presented in the ring opening metathesis (ROMP)-type polymer backbone. The formation of nanoparticles was revealed with UV-spectroscopy and Transmission Electron Microscopy (TEM). The presence of polyphosphonium ligand on the surface of the GNPs was confirmed by XPS and 31P NMR spectroscopy. Higher molecular weight polymer-GNPs exhibited better stability in the ambient conditions than the phosphonium polymers which possessed lower molecular weights. Phosphonium-based polymers can act, simultaneously, as reducing and stabilizing agents for the gold nanoparticles.