Infrared spectroscopy of the electrochemical double layer via electrode emersion

Abstract

AbstractInfrared reflection Spectroscopy was used via electrode emersion to study both adsorbed and non‐specifically adsorbing species within the electrochemical interphase on gold, ex situ. A cell was designed which allowed the electrode to rotate and continuously emerse from solution. The parallel‐polarized IR beam was reflected from the rotating surface above the solution at approximately 80°. FTIR spectra were taken of gold electrodes emersing from aqueous solutions of crystal violet, HCIO4, and D2SO4 at various electrode potentials, and ratioed as a function of potential. Active vibrational bands of crystal violet which strongly adsorbs to the gold, and of ClO4− and SO42− ions within the more ideally‐polarizable double layer, are easily seen. Changes in band intensities as a function of potential are, to first order, as expected.