Deposition of gold shell on polypyrrole coated poly(divinylbenzene) core

Poly(divinylbenzene) (PDVB) beads (2 ∼ 4 μm) were synthesized by precipitation polymerization and their surface was modified by introducing sulfonic acid groups to yield sulfonated PDVB (sPDVB). The sPDVB cores were initially coated with a polypyrrole (PPy) layer by chemical oxidative polymerization. In the process of formation of the gold shells, gold particles were deposited onto the previously prepared PPy-sPDVB cores as a seed material by in-situ redox reaction between Au(III) and neutral PPy and, then, uniform and smooth gold shells were gently grown on the cores by employing a electroless gold plating solution. The structure of the PPy-Au/PDVB core-shells was investigated by scanning electron microscopy (SEM). The presence of zero-valent gold was confirmed by X-ray photoelectron spectroscopy (XPS).