Insight into synergy for oxygen reduction electrocatalysis of iron-nitrogen-carbon

• Published in: Chem Vol. 10; no. 7; pp. 1994 - 2030
• Main Authors: Liu, Liqun, Rao, Xuebi, Zhang, Shiming, Zhang, Jiujun
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 11.07.2024
• Subjects: active sites; catalyst layers; Fe-N-C; oxygen reduction reaction; synergy; synthetic strategies; synergy; catalyst layers; active sites; oxygen reduction reaction; SDG7: Affordable and clean energy; synthetic strategies; Fe-N-C
• ISSN: 2451-9294; 2451-9294
• DOI: 10.1016/j.chempr.2024.06.006

Non-precious iron-nitrogen-carbon (Fe-N-C) catalysts are promising for replacing expensive and scarce platinum (Pt)-based catalysts for the oxygen reduction reaction (ORR) in polymer electrolyte fuel cells. However, their electrocatalytic ORR performance, including activity and stability, still cannot meet the practical demands. To make improvements, perceiving the synergistic effects can play an essential role in designing advanced Fe-N-C catalysts. In this paper, a comprehensive insight into synergy for the ORR electrocatalysis of Fe-N-C catalysts is reviewed, which permeates into three aspects: synergy in synthetic strategies to increase site density, enhance intrinsic activity, and improve catalyst stability; synergy in active sites involving Fe-based sites, non-metallic sites, and peripheral environments; and synergy in catalyst layers, including the catalyst body, ionomers, and additives. This review can provide profound viewpoints on the synergy for the efficient oxygen reduction electrocatalysis of Fe-N-C catalysts and, therefore, effectively guide the development of high-performance, non-noble carbon-based catalysts and their reliable applications in electrochemical energy technologies. [Display omitted] Electrochemical energy technologies, including the promising proton/anion exchange membrane fuel cells, have shown great potential in alleviating energy shortages and reducing environmental pollutants. However, platinum (Pt) is necessary to catalyze the sluggish oxygen reduction reaction (ORR), but this is still substantially subject to its scarce reserves and limited availability. Iron-nitrogen-carbon (Fe-N-C) materials appear as the most advanced and promising non-precious catalysts. However, both their activity and stability are still insufficient. As summarized in this review, perceiving the synergistic effects from three aspects of synthetic strategies, active sites, and catalyst layers will play an important role in designing the advanced Fe-N-C catalysts and promoting their practical applications. We hope this review can provide comprehensive insights into synergy for ORR electrocatalysis to develop efficient and practical Fe-N-C catalysts for electrochemical energy technologies. Liu et al. proposed a comprehensive insight into the synergy for the efficient oxygen reduction electrocatalysis of iron-nitrogen-carbon (Fe-N-C) catalysts. In this review, synergistic effects have been summarized systematically, involving three aspects of synthetic strategies, active sites, and catalyst layers. A profound understanding of synergy will open up new ideas for the precise design of high-performance, non-noble carbon-based electrocatalysts and their practical application in electrochemical energy technologies.