Optically monitored wet-chemical preparation of SEIRA active Au nanostructures

The growth process of spherical substrate-bound Au nanoparticles (AuNP) was investigated within situ visible (VIS) spectroscopy, in situ Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). In the VIS spectra, the redshift and broadening of the AuNP's surface plasmon resonance could be observed, as the size of the AuNP increased. FTIR spectra showed the increasing IR absorption of the surrounding water molecules because of the surface-enhanced infrared absorption (SEIRA), as well as plasmon absorption. IR spectra of adsorbates were further used to compare the SEIRA activity of the resulting Au films. Copyright (C) 2008 John Wiley & Sons, Ltd.