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 jpr/jpf (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 jpr/jpf will give the more stable performance of methanol oxidation on the Pd-oxide/C. The value of jpr/jpf 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 jpr/jpf on them are very high, so performance of methanol oxidation on the Pd–Co3O4/C and Pd–NiO/C is not stable.

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► The firstly report the different between stability and activity for the Pd-oxide catalyst.
► The more small value of jpr/jpf is, the more stable performance of methanol oxidation on the Pd-oxide/C is.
► Pd–Mn3O4/C is the best stable catalyst due to the value of jpr/jpf is the smallest.
► The Pd–Co3O4/C and Pd–NiO/C give a high activity, however they are not stable catalysts due to the values of jpr/jpf are high.