Abstract
Au nanoparticles coated with silica layer were self-assembled on a glass substrate. Au particles with the diameter of about 15 nm were prepared by the thermal-reduction method using citrate as a protective agent, followed by immersing in the sodiumsilicate solution to form the silica around the Au particles. The thickness of silica layer was changed by the immersing temperature and period in solution.The obtained silica-coated Au particles were self-assembled on the glass substrate coupled with poly(diallyldimethylammoniumchloride) (PDDA), forming a closed-packing monolayer film.The self-assembled Au nanoparticles exhibited an optical absorption at 520 nm wavelength due to the surface plasmon resonance.
