The interpretation of solution electrolyte vibrational bands in potential-difference infrared spectroscopy

摘要: Abstract The influence of ionic migration to and from the surrounding solution reservoir upon potential-difference infrared (PDIR) spectra is examined for some cases involving anionic adsorption in order elucidate its consequences net potential-induced compositional changes thin-layer solution. Representative PDIR azide anions on gold are compared absence presence excess alkali perchlorate supporting electrolyte. In latter, loss spectral thin layer stepping a more positive potential, resulting increased adsorption, accompanied by extensive into layer. form induced potential-dependent specific differs these two circumstances since former between cavity necessary charge compensation provided electrolyte itself, whereas latter case yields fixed quantity intensities sign bands arising solution-phase enable extent redistribution be quantified. added perchlorate, magnitude band diminished substantially, inferring that replenishment concentration occurs predominantly via N − 3 reservoir. Similar results were also obtained cyanate gold. cation as well anion this was employing an infrared-active cation, NH + 4 , addition H O . While indicate can contribute substantially redistribution, typically appears predominate when encountered. Some general such ion effects interpretation noted.