Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7731154 | Journal of Power Sources | 2015 | 12 Pages |
Abstract
Due to the wide applications of acetonitrile as a solvent in the chemical industry, acetonitrile can be present in the air and should be considered a possible pollutant. In this work, the spatial proton exchange membrane fuel cell performance exposed to air with 20Â ppm CH3CN was studied using a segmented cell system. The injection of CH3CN led to performance losses of 380Â mV at 0.2Â AÂ cmâ2 and 290Â mV at 1.0Â AÂ cmâ2 accompanied by a significant change in the current density distribution. The observed local currents behavior is likely attributed to acetonitrile chemisorption and the subsequent two consecutive reduction/oxidation reactions. The hydrolysis of CH3CN and its intermediate imine species resulted in NH4+ formation, which increased the high-frequency resistance of the cell and affected oxygen reduction and performance. Other products of hydrolysis can be oxidized to CO2 under the operating conditions. The reintroduction of pure air completely recovered cell performance within 4Â h at 1.0Â AÂ cmâ2, while at 0.2Â AÂ cmâ2 the cell recovery was only partial. A detailed analysis of the current density distribution, its correlation with spatial electrochemical impedance spectroscopy data, possible CH3CN oxidation/reduction mechanisms and mitigation strategies are presented and discussed.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Tatyana V. Reshetenko, Jean St-Pierre,