Catalytic combustion of hydrogen over La1-xSrxCoO3-delta + Co3O4 and LaMn1-xCuxO3+delta under simulated MCFC anode off-gas conditions

Abstract

The activities of two perovskite catalysts, LaMn1-xCuxO3+delta (O <= x <= 1) and La1-xSrxCoO3-delta (0 <= x <= 1), were tested for the catalytic combustion of hydrogen under simulated molten carbonate fuel cell (MCFC) anode off-gas conditions. The catalysts were prepared using the sol-gel citrate (SGC) method and were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, oxygen temperature-programmed desorption (O-2-TPD), and temperature-programmed reduction (TPR) in order to discriminate the major properties governing the activities of the catalysts. The activity of LaMn1-xCuxO3+delta was the highest at x = 0.4, at which the reducibility of B-site cations and mobility of active oxygen were the most prominent. The activity of La1-xSrxCoO3-delta was strongly related to the amount of oxygen vacancies, and the by-produced Co3O4 had a positive effect, which was the reason why the catalyst at x=0.6 (a mixture of La1-xSrxCoO3-delta + Co3O4) was comparatively active to those at x = 0.2 and 0.4. (C) 2011 Elsevier B.V. All rights reserved.