Boron and Fluorine Co-Doped Graphene/Few-Walled Carbon Nanotube Composite as Highly Active Electrocatalyst for Oxygen Reduction Reaction

Kurzfassung

Functionalization of nanocarbon materials with heteroatoms is of paramount interest as doping of carbon with electron withdrawing groups results in change of electrochemical properties of the potential catalyst. Adding fluorine, as the most electronegative element into the doping process next to boron is expected to have significant effect on the design of novel nanocarbon-based electrocatalysts. In this paper boron and fluorine co-doped reduced graphene oxide/few-walled carbon nanotube (BF-rGO/FWCNT) catalysts are synthesized via simple and low-cost direct pyrolysis method using boron trifluoride diethyl etherate (BTDE). Composition analysis confirmed that boron and fluorine have been grafted onto the carbon support. Rotating disk electrode (RDE) measurements revealed that BF-rGO/FWCNT has remarkable electrocatalytic activity toward the oxygen reduction reaction (ORR) both in alkaline and acid media. The onset potential of the best BF-rGO/FWCNT catalyst was 50 mV more positive in alkaline and 600 mV more positive in acidic media compared with un-doped rGO/FWCNT. The half-wave potential was 100 mV more positive in alkaline media and 700 mV more positive in acidic media in comparison with undoped rGO/FWCNT.