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Direct Metallization of Gold Nanoparticles on a Polystyrene Bead Surface using Cationic Gold Ligands
Author(s) -
Lee JunHo,
Kim Dong Ouk,
Song GyuSeok,
Lee Youngkwan,
Jung SeungBoo,
Nam JaeDo
Publication year - 2007
Publication title -
macromolecular rapid communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.348
H-Index - 154
eISSN - 1521-3927
pISSN - 1022-1336
DOI - 10.1002/marc.200600757
Subject(s) - cationic polymerization , polystyrene , colloidal gold , polymer , adsorption , materials science , nanoparticle , ion exchange , chemical engineering , surface modification , dispersion (optics) , polymerization , polymer chemistry , ligand (biochemistry) , chemistry , ion , nanotechnology , composite material , organic chemistry , biochemistry , physics , receptor , optics , engineering
Gold nanoparticles are formed to cover the surface of sulfonated‐polystyrene (PS) beads by the in‐situ ion‐exchange and chemical reduction of a stable cationic gold ligand, which makes it different from the physical adsorption or multiple electroless metallization methods. PS beads are synthesized by dispersion polymerization with a diameter of 2.7 µm, and their surface is modified by introducing sulfonic acid groups (SO 3 − ) to give an ion exchange capacity of up to 2.25 mequiv. · g −1 , which provides 1.289 × 10 10 SO 3 −per bead. Subsequently, the anionic surface of the PS beads is incorporated with a cationic gold ligand, dichlorophenanthrolinegold(III) chloride ([AuCl 2 (phen)]Cl), through an electrostatic interaction in the liquid phase to give gold nanoparticles (ca. 1–4 nm in diameter) formed on the PS surface. Assuming that approximately three SO 3 −groups interact with one [AuCl 2 (phen)] + ion in the ion‐exchange process, the gold coverage on a PS bead is estimated as 12.0 wt.‐%, which compares well with the 16.8 wt.‐% of gold loading measured by inductively coupled plasma–mass spectrometry. Because of the adjustable IEC values of the polymer surface and the in‐situ metallization of Au in the presence of S atoms, both of which are of a soft nature, the developed methodology could provide a simple and controllable route to synthesize a robust metal coating on the polymer bead surface.