Fluorine-Doped Nanocarbon-Based Materials for Aqueous Oxygen Electrocatalysis: Synthesis, Mechanisms, Applications, and Perspectives

Abstract Oxygen electrocatalysis, involving the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), is central to rechargeable metal-air batteries, fuel cells, and electrochemical H2O2 production. Fluorine (F)-doped nanocarbon-based materials (F-DNCMs) have emerged as promising alternatives to noble-metal electrocatalysts because the high electronegativity of the F atom enables strong modulation of the electronic structure of carbon frameworks. F incorporation can polarize adjacent carbon atoms, redistribute charge density, regulate the adsorption energetics of oxygen intermediates, and generate defects/edge sites, thereby improving ORR/OER kinetics. Despite these advantages, a comprehensive review of F-doped nanocarbon-based materials (F-DNCMs) for oxygen electrocatalysis remains lacking. This Review systematically summarizes recent progress in the synthesis, structural regulation, catalytic mechanisms, and applications of F-DNCMs. Representative fluorination strategies are presented and compared in terms of their characteristics, advantages, and limitations. F-DNCMs are further classified into F single-doped carbons, F-based dual-doped and multidoped carbons, and F-doped carbon-based hybrids, with emphasis on the effects of C−F bonding configurations, charge polarization, defect engineering, interfacial coupling, and heteroatom synergy on ORR/OER performance. Besides, their applications in metal-air batteries, fuel cells, and electrochemical H2O2 production are also highlighted. Finally, key challenges in precise control of F species, identification of active sites, scalable synthesis, and device integration are discussed. This Review aims to establish structure-property-activity relationships and provide practical guidance for the rational design of high-performance F-DNCM electrocatalysts.