Surface-Pt-rich AgPtAu trimetallic nanotrough arrays for boosting alcohol electrooxidation

Abstract

To develop high-performance low-Pt electrocatalysts for direct alcohol fuel cells (DAFCs), we herein propose an interfacial engineering strategy, using interfacial Ag nanowire arrays as a sacrificing template and successfully fabricating a AgPtAu nanotrough array catalyst at water/air interfaces. By adjusting the conditions of interfacial reaction, composition-varied AgPtAu nanotrough arrays can be easily obtained. The formation of a trough-like morphology of AgPtAu can be attributed to the interface-confined Ag nanowire arrays reacting successively with PtCl₆²⁻ and AuCl₄⁻ in the water phase. Optimized surface-Pt-rich Ag₁₁Pt₅Au₈₄ nanotrough arrays exhibit ∼2270 and ∼2290 mA mg_Au+Pt⁻¹ in the mass activity towards methanol and ethanol electrooxidation, respectively, ∼3 times better than that of commercial Pt/C, and show improved tolerance towards CO-like carbonaceous intermediates. This work suggests that properly combining the positive catalytic effects of morphology and composition may be a possible avenue to tackle the issue of low-Pt electrocatalysts for DAFCs.