In this study, we demonstrate a novel approach;atomic layer deposition (ALD);for the synthesis
and investigation of Pt-Ru catalyst structures toward the oxidation of stoichiometric (1:1)
methanol solutions in advanced direct methanol fuel cells. Two types of thin-film materials are
investigated as catalysts for methanol oxidation: Pt-Ru films of varying ruthenium content that are
co-deposited by ALD, and Pt skin catalysts made by depositing porous platinum layers of different
thickness byALDon sputtered ruthenium films. MeCpPtMe3 and Ru(Cp)2 are used as precursors for
Pt and Ru ALD, respectively, together with pure O2 as the counter reactant. The electrochemical
behavior of the co-deposited Pt-Ru catalysts and the Pt skin catalysts for methanol oxidation is
characterized using chronoamperometry and cyclic voltammetry in a 0.5MH2SO4/16.6MCH3OH
electrolyte at room temperature. The results illustrate that the optimal stoichiometric Pt:Ru ratio for
the co-deposited catalysts is ∼1:1, which is consistent with our previous study on sputtered Pt-Ru
catalysts using the same CH3OH concentration. Moreover, we report that the catalytic activity of
sputtered ruthenium catalysts toward methanol oxidation is strongly enhanced by the ALD Pt
overlayer, with such skin catalysts displaying superior catalytic activity over pure platinum. The
mechanistic aspects of our observations are discussed. SP-200便携式电化学工作站
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