Noble-Metal-Free FeMn-N-C catalyst for efficient oxygen reduction reaction in both alkaline and acidic media

The oxygen reduction reaction (ORR) is important cathodic reaction running in several electrochemical energy conversion devices. It is still difficult to develop non-precious nanocatalysts for ORR that have high activity and increased durability for practical application. Herein, bimetallic FeMn(mIm)-N-C composite incorporated with Fe and Mn via an encapsulation-ligand exchange technique is prepared and established as an efficient ORR catalyst. The results reveal that FeMn(mIm)-N-C shows outstanding ORR performance with E1/2 of 0.861 V and 0.778 V in alkaline and acid solutions, along with robust durability. Additionally, the assembled Zn-Air batteries (ZAB) and proton exchange membrane fuel cells (PEMFCs) both have exceptional power densities and show promise for long-term stability compared to 20% Pt/C. The present work provides a useful strategy for designing and synthesizing a reliable lowcost and high-efficient electrocatalysts for energy conversion and storage.(c) 2023 Elsevier Inc. All rights reserved.

Automated summary

A bimetallic FeMn(mIm)-N-C composite with encapsulation-ligand exchange technique is prepared as an efficient ORR catalyst, showing outstanding performance and durability. It exhibits E1/2 values of 0.861 V and 0.778 V in alkaline and acid solutions, and demonstrates exceptional power densities and long-term stability in assembled Zn-Air batteries and proton exchange membrane fuel cells compared to 20% Pt/C.