Design and application of metal-organic framework-derived catalysts for oxygen reduction in energy conversion devices

Abstract

The oxygen reduction reaction (ORR) is a clean energy conversion process with the potential to address the current energy crisis and promote the adoption of clean energy sources. Developing high-activity catalysts is essential to accelerate the inherently slow ORR kinetics and improve overall efficiency. Atomic-level oxygen reduction catalysts can be prepared through pyrolysis and solvothermal synthesis, using metal-organic frameworks (MOFs) as precursors or templates. This approach preserves the structural advantages of MOFs while enabling precise, atomic-scale tuning of catalyst composition and structure, thereby optimizing their ORR catalytic performance. Advances in catalyst synthesis and characterization methods have improved the understanding of the dynamic evolution of active centers and ORR performance in real-world devices. This paper provides a comprehensive review of ORR mechanisms, describes MOF-derived ORR catalytic materials with distinct ligands, and classifies them by ligand type to elaborate on the role of ligands in catalyst derivation and their influence on ORR performance. It further discusses the tuning of various MOF-derived catalyst types-single-atom, dual-atom, and cluster configurations-through precise control of metal content and species, exploring the relationship between catalyst architecture and ORR activity. The challenges of real-time monitoring of MOF pyrolysis and of understanding dynamic metal coordination during catalytic processes are also discussed. Finally, it examines the future prospects and challenges of MOF-based catalysts for the ORR.

Keywords

Oxygen reduction reaction / fuel cells / Zn-air batteries / metal-organic frameworks / MOF-derived materials / electrocatalysts

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