Effects of Secondary Metals on Platinum-Based Nanoparticles Supported by Mesoporous Nitrogen-Doped Carbon toward Oxygen Electro-Reduction

Platinum (Pt)-based alloy nanoparticles have demonstrated significantly improved performance for the oxygen reduction reaction (ORR). Recently, the innovation of their support materials has attracted increasing attention─the second-generation Toyota Mirai fuel cell adopts mesoporous carbon supporting PtCo alloys at the cathodes. Herein, an emerging ZIF-derived nitrogen-doped mesoporous carbon is used as a support, and the effects of secondary metals, including Co, Fe, Ni, and Cu, on the Pt-based nanoparticles are investigated in terms of the nanoparticle formation, their interaction with the support, ORR activity, etc. The experimental results indicate that the type of secondary metal significantly influences the nanoparticle size distribution, alloying degree, and reasonably the electrochemical surface area, while the Pt–N bond over different Pt-based nanoparticles and supports determines the ORR intrinsic activity. This work provides insights into the design and synthesis of Pt-based alloying nanoparticles loaded on a N-doped mesoporous carbon support.