Stability analysis of oxide (CeO2, NiO, Co3O4 and Mn3O4) effect on Pd/C for methanol oxidation in alkaline medium

The relationship between the value of j(pr)/j(pf) (ratio of peak current densities in the reverse sweep and the forward sweep) and stability for methanol oxidation on oxide (CeO2, NiO, Co3O4 and Mn3O4)-promoted Pd/C electrocatalysts in alkaline medium has been investigated. The smaller value of j(pr)/j(pf) will give the more stable performance of methanol oxidation on the Pd-oxide/C. The value of j(pr)/j(pf) on the Pd-Mn3O4/C is the smallest and much smaller than that on the other Pd-oxide/C, so the Pd-Mn3O4/C is the best stable catalyst and gives the best stable performance of methanol oxidation. The Pd-Co3O4/C and Pd-NiO/C give much higher catalytic activity than the other Pd-oxide/C electrocatalysts, however the values of j(pr)/j(pf) on them are very high, so performance of methanol oxidation on the Pd-Co3O4/C and Pd-NiO/C is not stable. (c) 2012 Elsevier Ltd. All rights reserved.