Surface Enhanced Raman Spectra from the Films Formed on Nickel in the Passive and Transpassive Regions

Abstract

Surface enhanced Raman (SER) spectra were obtained from nickel electrodes immersed in borate buffer solution (pH 8.4) at +600, and +900 mV(SCE) using electrodeposited gold particles to produce the surface enhancement effect. Comparison with earlier experiments performed using silver particles to obtain SERS indicates that the spectra of the nickel passive films are identical regardless of whether silver or gold is used. At +100 mV, the nickel passive film consists of amorphous ; is not observed. At +600 mV, amorphous persists, and Au‐O forms on the gold particles. The SER spectrum of the transpassive film formed on nickel at +900 mV consists of peaks located at 480 and 560 cm−1, and it is speculated that the species responsible for the Raman scattering resembles . Upon returning the potential to +100 mV from +900 mV, reforms, accompanied by . This is the first example of the use of gold particles to explore the passive film of nickel and the first time the SER spectrum of the transpassive film on nickel has been measured.