Precisely tuning the electronic structure of a structurally ordered PtCoFe alloy via a dual-component promoter strategy for oxygen reduction

Abstract

Optimizing the electronic structure of Pt-based alloys has emerged as an effective strategy to further improve their catalytic oxygen reduction reaction (ORR) performance, yet this remains challenging. Here, we have successfully tuned the electronic structure of ordered PtCoFe nanoparticles by incorporating the third component (Fe) into a bimetallic ordered PtCo alloy and manipulating its content. With the merits of the optimum electronic structure and the favorable composition, as well as the robust ordered structure, the as-prepared ordered PtCoFe-1-0.6 alloy (1 and 0.6 represent the feeding molar ratio of Co to Pt and Fe to Pt, respectively) exhibits enhanced catalytic performance for ORR. The L1₀-PtCoFe-1-0.6 alloy delivers higher specific activity (2.23 mA cm⁻²) than bimetallic L1₀-PtCo-1 (1.34 mA cm⁻²) and the commercial Pt/C (0.23 mA cm⁻²) catalyst. Indeed, this dual-catalytic-component promoter strategy gives a significant insight into developing high-performance homogeneous catalysts.