Synthesis of Nanoporous Au−Cu−Pt Alloy as a Superior Catalyst for the Methanol Oxidation Reaction

A nanoporous (np) Au−Cu−Pt thin‐film catalyst with a fine structure and tunable composition is synthesized by using a facile method involving successive electrodeposition and de‐alloying. The structure, electronic state, elemental content, and active surface area of the catalyst, along with the Pt fraction, are characterized and/or determined before and after the methanol oxidation reaction (MOR) tests through electrochemical and ultrahigh vacuum analytical routines. The prepared np Au−Cu−(8 % in the precursor alloy)Pt catalyst exhibits outstanding mass and specific activity toward the MOR, which is approximately six‐ and nine‐times higher than the activity of a commercial Pt/C(40 %) counterpart, respectively. A negative 75 mV onset potential shift upon the MOR anodic scan on the np Au−Cu−(8 %)Pt catalyst in comparison with Pt/C(40 %) corroborates its higher catalytic activity. Furthermore, the alloy catalyst demonstrates better durability than the Pt/C(40 %) counterpart in a three‐hour constant potential test and exhibits full post‐factum recovery of its cycling activity. In addition, it retains more than 60 % of its original activity after 3000 cycles of an accelerated degradation test. The outstanding performance is attributed to the specific catalyst's structure leading to a d‐band upshift along with unique constituent interplay.