Surface-enhanced Raman scattering (SERS) on modified amorphous Cu-Zr alloys

Partially devitrified Cu-Zr amorphous alloys with 50 at% of Cu and Zr were used as targets for in situ SERS measurements of adsorbed pyridine. We have found that large SERS signals are measured from the Cu-rich domains, where as the intensity drops down by one order of magnitude on the Zr-rich areas. Moreover, the effect of electrode potential on the SERS signal for various surface domains (of about 1 mu m(2)) is very different one from another wh ich suggests that the activity of various Cu clusters present at different surface sites differs accordingly, one from another. These results show tha t SERS, particularly if coupled with the Raman microscope, could be a usefu l method for studying the adsorption of molecules in Cu containing catalyst s because of its high sensitivity to the physical and chemical states of th e substrate. (C) 1999 Elsevier Science S.A. All rights reserved.