Bimetallic CuCo@Nitrogen/Carbon Nanoparticles as a Cathode Catalyst for Magnesium‐Air Batteries

Abstract Mg‐air batteries are regarded as one of the most promising electrochemical energy storage and conversion devices. Developing high‐performance, low‐cost and durable non‐noble metal electrocatalysts for oxygen reduction reaction (ORR) at cathode is extremely critical for promoting the practical applications of Mg‐air batteries. The bimetallic M−N−C catalysts possess the superior ORR activity and stability due to the synergetic effect of metal atoms. Herein, prussian blue analogues (PBA) were employed as precursors to prepare bimetallic M−N−C electrocatalysts. The CuCo@N/C and Co@N/C were derived from CuCo−PBA and CoCo−PBA calcined under different temperatures. The bimetallic CuCo@N/C nanoparticles pyrolyzed at 800 °C (CuCo@N/C‐800) displays superior ORR performances and outstanding stability in alkaline and neutral electrolytes. The primary Mg‐air batteries assembled with the CuCo@N/C‐800 as the cathode catalyst displays better discharge performances than that of Co@N/C‐800. This work provides an effective strategy to synthesize bimetallic and non‐noble ORR catalysts for Mg‐air batteries.