Infrared Spectrum of CO on a Platinum Electrode in Acidic Solution

Polarization-modulated infrared reflection absorption spectroscopy has been used to measure the spectrum of adsorbed CO on a Pt electrode in both 1 M H sub 2 SO sub 4 and 1 M HClO sub 4 saturated with CO gas. This is the first direct measurement of the infrared band of adsorbed CO on an active electrode and definitively establishes the dependence of the band wave number on electrode potential as the primary source of the unusual bisignate band previously observed with electrode-modulated infrared spectroscopy.--AA