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Advantage of semi-ionic bonding in fluorine-doped carbon materials for the oxygen evolution reaction in alkaline media.

ABSTRACT: Metal-free carbonaceous catalysts have potential applications for oxygen evolution reaction (OER) devices because of their low-cost and abundant supply. We report that fluorine-doped carbon black is an active catalyst for OER. Fluorine-doped carbon black (F-KB) is simply synthesized by the pyrolysis of KETJENBLACK (KB) as carbon substrate with Nafion as fluorine precursor. As a result, the OER activity of F-KB is significantly higher than that of pristine KB in alkaline media. The OER catalytic activity of F-KB is found to be dependent on the quantity and characteristics of carbon-fluorine bonding (C-F) which can be controlled by the pyrolysis temperature. It is further found that the OER activity depends on the quantity of semi-ionic C-F bonds, but not covalent C-F bonds. This result proves the importance of carbon atoms with semi-ionic C-F bonds as the active sites for OER.

SUBMITTER: Kim J

PROVIDER: S-EPMC9079933 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Advantage of semi-ionic bonding in fluorine-doped carbon materials for the oxygen evolution reaction in alkaline media.

Kim Jeheon J Zhou Ruifeng R Murakoshi Kei K Yasuda Satoshi S

RSC advances 20180417 26

Metal-free carbonaceous catalysts have potential applications for oxygen evolution reaction (OER) devices because of their low-cost and abundant supply. We report that fluorine-doped carbon black is an active catalyst for OER. Fluorine-doped carbon black (F-KB) is simply synthesized by the pyrolysis of KETJENBLACK (KB) as carbon substrate with Nafion as fluorine precursor. As a result, the OER activity of F-KB is significantly higher than that of pristine KB in alkaline media. The OER catalytic ...[more]

PMID: 35540778

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