Engineering an Ultrahigh-Surface-Area Diatomic Catalyst via Two-Dimensional-Templated Vapor-Deposition for Advanced...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Rechargeable zinc-air batteries (ZABs) show promise for energy storage but are limited by slow oxygen reduction reaction (ORR) kinetics.
• Developing efficient and stable catalysts is crucial for advancing ZAB technology.

Purpose of the Study:

• To design and synthesize a high-performance diatomic catalyst for the ORR in ZABs.
• To investigate the catalytic mechanism and performance of atomically dispersed Fe-Cu pairs on nitrogen-doped carbon (FeCu/NC).

Main Methods:

• Synthesis of FeCu/NC using a two-dimensional-templated vapor-deposition approach.
• Characterization of the catalyst's structure, surface area, and composition.
• Electrochemical evaluation of ORR activity in alkaline media and performance testing in ZABs.

Main Results:

• FeCu/NC exhibited a high specific surface area (1800 m² g⁻¹), facilitating mass transport.
• The catalyst achieved an exceptional ORR half-wave potential of 0.912 V, outperforming single-atom catalysts and commercial Pt/C.
• Electronic coupling between Fe and Cu atoms was identified as key to lowering the O-O bond cleavage barrier.
• ZABs utilizing FeCu/NC demonstrated high power density and extended cycling stability.

Conclusions:

• Atomically dispersed Fe-Cu pairs on nitrogen-doped carbon represent a breakthrough catalyst for ZABs.
• Heteronuclear electronic coupling within a high-surface-area architecture is an effective strategy for designing advanced ORR catalysts.
• This work paves the way for improved catalysts in energy conversion applications.