Microinjection-assisted synthesis of Pt–Pd hollow nanoparticles for enhanced methanol oxidation reactions†

A large-scale synthesis of electrocatalysts with controllable composition and a surface atomic structure is crucial for practical applications. Herein, Pt–Pd hollow nanoparticles (HNs) were prepared using a facile microinjection strategy. Owing to their high-density nanopores, atomic steps and grain boundaries, the Pt–Pd HNs exhibit a superior catalytic activity for the methanol oxidation reaction (MOR) compared with commercial Pt black. Moreover, theoretical calculation proves that compared with the Pt and Pd structures, the Pt–Pd alloy structure possesses high anti-CO poisoning capability and a low energy barrier in the rate-limiting step, both of which are favorable for the MOR. This work proposes a strategy for large-scale preparation of hollow electrocatalysts with high catalytic activity, thus promoting practical application of direct methanol fuel cells (DMFCs).