Contamination of Pt Catalyst with Carbon Monoxide during Hydrogen Evolution

Effect of carbon monoxide (CO) on the hydrogen evolution reaction (HER) on Pt electrode is investigated. Electrochemical hydrogen pump (EHP) cells are exposed to CO in hydrogen (H 2 ) on the HER electrode with pure H 2 maintained in the hydrogen oxidation reaction (HOR) electrode. Cyclic voltammetry is utilized to measure carbon monoxide coverage on the catalyst surface. Chemical adsorption and desorption are the dominant mechanisms to determine CO coverage on the HER electrode; hydrogen evaluation reaction has minimal effect on the CO coverage, and CO coverage has minimal impact on the HER rate unlike the HOR.