Enhancing oxygen reduction performance of oxide-CNT through in-situ generated nanoalloy bridging

Abstract Platinum group metal (PGM)-free catalysts for oxygen reduction reaction (ORR) are highly craved in fuel cells and battery applications. Herein, a group of hybrid electrocatalysts is synthesized through a facile one-step treatment of perovskite oxide, D-glucosamine hydrochloride and melamine. The high-performance catalyst comprises an unique hybrid architecture, including the mixed oxide substrate derived from perovskite oxide, the in-situ exsolved NiCo nanoalloys, and the nitrogen doped carbon nanotubes (NCNT) grown from the aforementioned nanoalloy particles. The dispersed NiCo nanoalloy serves as a liaison for efficient charge transfer between metal oxides and NCNT, and thus manages to unlock the high intrinsic activity of the metal oxide-based materials. The hybrid catalyst delivers a promising ORR activity, durability and methanol poisoning tolerance comparable to the expensive benchmark Pt/C catalyst. The zinc-air battery using the hybrid catalyst demonstrates a high open circuit voltage of 1.57 V with a maximum power density of 115 mW cm-2.