Highly Active and Durable Pt₇₂Ru₂₈ Porous Nanoalloy Assembled with Sub‐4.0 nm Particles for Methanol Oxidation

Abstract

The main challenges to the direct methanol fuel cells are the activity and durability of electrocatalysts. To alleviate such issues, a recently proposed strategy introduces an exotic element to form Pt‐based alloy nanostructures. This study reports a green route to prepare porous flowerlike Pt 72 Ru 28 nanoalloys assembled with sub‐4.0 nm particles. The peak current density and mass activity on these as‐synthesized porous flowerlike Pt 72 Ru 28 nanoalloys can be increased to 10.98 mA cm −2 and 1.70 A mg −1 Pt for methanol oxidation in acidic medium. They are respectively 4.19/3.54, 4.27/5.0, and 5.74/1.73 times those on the commercial Pt black, Pt 50 Ru 50 black, and Ru 50 Pt 50 /C. These porous flowerlike Pt 72 Ru 28 nanoalloys have a much higher long‐term durability than commercial Pt black, Pt 50 Ru 50 black, and Ru 50 Pt 50 /C. More significantly, the porous Pt 72 Ru 28 bimetallic nanoalloys have long‐term solvent durability after immersion in water for 16 months. The peak current density and mass activity on porous Pt 72 Ru 28 nanoalloys are still 7.76 mA cm −2 and 1.2 A mg −1 Pt. These experimental results show an effective approach to the development of PtRu nanoalloys as electrocatalysts with substantially enhanced activity and durability for direct methanol fuel cells.