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, whereas 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 μm2) is very different one from another which suggests that the activity of various Cu clusters present at different surface sites differs accordingly, one from another. These results show that SERS, particularly if coupled with the Raman microscope, could be a useful method for studying the adsorption of molecules in Cu containing catalysts because of its high sensitivity to the physical and chemical states of the substrate.