Carbon-loaded ordered PdZn alloys for efficient oxygen reduction in zinc–air batteries

Abstract

The fabrication of ordered noble metal alloys on carbon supports can effectively alter the electronic structure of the catalyst interface and the valence states of the elements, presenting a viable alternative to platinum (Pt) for the electrocatalysis of the oxygen reduction reaction (ORR) in metal–air battery cathodes. Herein, we developed a straightforward in situ reduction synthesis method that facilitates the formation of ordered PdZn alloy catalysts on hollow carbon under specific conditions, optimizing ORR efficiency. In an oxygen-saturated 0.1 M KOH solution, the ORR performance of the synthesized Pd_0.02Zn-NC-900 catalyst exhibits an initial potential of ∼0.996 V and a half-wave potential of ∼0.887 V at 1600 rpm. When integrated into a zinc–air battery, it achieves a remarkable specific power of 213.7 mW cm⁻² and a specific capacity of 813.8 $\mathrm{mAh}{g}_{\mathrm{Zn}}^{-1}$, outperforming commercial Pt/C. Our research focuses on the efficient synthesis of carbon-supported ordered PdZn alloys to address the needs of electrochemical energy conversion applications.