On-line mass spectrometry study of electrochemical corrosion of the graphite electrode for vanadium redox flow battery

The electrochemical corrosion of the graphite electrode for vanadium redox flow battery is investigated by on-line mass spectrometry analysis. The results show that CO2 and CO form and evolve more preferably than O-2 on the graphite anode, which lead to the electrochemical corrosion of the graphite electrode. Furthermore, the evolution rate of O-2 is the highest one among evolved gases if the polarization potential becomes too positive. The oxidation of VO2+ on the graphite electrode in 2 M H2SO4 + 2 M VOSO4 hinders the carbon oxidation reaction and retards the electrochemical corrosion of the graphite electrode. (C) 2012 Elsevier B.V. All rights reserved.