Fluorine-Doped Carbon Blacks: Highly Efficient Metal-Free\nElectrocatalysts for Oxygen Reduction Reaction

Abstract

For\nthe goal of practical industrial development of fuel cells,\ninexpensive, sustainable, and high performance electrocatalysts for\noxygen reduction reactions (ORR) are highly desirable alternatives\nto platinum (Pt) and other rare materials. In this work, sustainable\nfluorine (F)-doped carbon blacks (CB-F) as metal-free, low-cost, and\nhigh-performance electrocatalysts for ORR were synthesized for the\nfirst time. The performance (electrocatalytic activity, long-term\noperation stability, and tolerance to poisons) of the best one (BP-18F,\nbased on Black Pearls 2000 (BP)) is on the same level as Pt-based\nor other best non-Pt-based catalysts in alkaline medium. The maximum\npower density of alkaline direct methanol fuel cell with BP-18F as\nthe cathode (3 mg/cm²) is ∼15.56 mW/cm² at 60 °C, compared with a maximum of 9.44 mW/cm² for commercial Pt/C (3 mg_Pt/cm²). All these\nresults unambiguously demonstrate that these sustainable CB-F catalysts\nare the most promising alternatives to Pt in an alkaline fuel cell.\nSince sustainable carbon blacks are 10 000 times less expensive\nand much more abundant than Pt or other rare materials, these CB-F\nelectrocatalysts possess the best price/performance ratio for ORR\nto date.