Recent Advances in Metal-Organic Frameworks for Li-O2 Batteries: Advantages, Challenges, and Innovative Design

Abstract

Metal-Organic Frameworks (MOFs) have emerged as promising candidates for cathode materials in Li-O2 batteries due to their exceptional properties such as high surface area, periodic porous structures, tunable pore sizes, and controllable chemical compositions. This review highlights the innovative designs of MOFs, focusing on the central metal contributing to the oxygen reduction reaction (ORR)/oxygen precipitation reaction (OER) kinetics. In addition, the impact of organic ligand design, bimetallic/heterometallic node engineering, defect introduction, and hybrid material strategies are discussed, each providing new avenues to improve catalytic activity, electron/mass transport, and long-term durability. With the advancement of photo-assisted Li-O2 cells and the semiconducting properties of MOF materials, this review also underscores the application of MOFs in photo-assisted Li-O2 batteries. Furthermore, the latest progress in MOF-based solid-state electrolytes for Li-O2 batteries is covered, demonstrating how their hierarchical porous structure and strong mechanical/chemical stability substantially boost lithium-ion conductivity and battery safety. Finally, future research directions are proposed, stressing the necessity for integrated approaches that combine MOFs with other materials to further enhance the efficiency and longevity of Li-O2 batteries.