Kinetics of fluorine evolution reaction on carbon anodes: influence of the surface C-F films
Kinetics of fluorine evolution reaction on carbon anodes: influence of the surface C-F films
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DOI：
10.1016/s0022-1139(00)00366-3
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发表时间：
2001-02-01
影响因子：
1.9
通讯作者：
Lantelme, F
中科院分区：
文献类型：
--
作者：
Groult, H;Durand-Vidal, S;Lantelme, F
在熔融KF-2 HF的电解析氟反应期间，在碳阳极上形成薄的固体氟碳层。该膜主要由氟石墨层间化合物和少量绝缘性氟化石墨组成。在汞中进行的阻抗测量和在含有氧化还原对的水溶液中的循环伏安法研究表明，表面他表现得像一个电子导体，不能构成一个高能量的障碍，在电化学反应中的电子转移。然而，氟析出反应的动力学强烈依赖于KF-2 HF中的水含量，实际上，水有助于限制氟析出反应的氟化石墨的形成。STM测量原油和钝化的高取向热解石墨（HOPG）样品进行了指出，这种碳-氟他和水的影响的组成的不均匀性。已经表明，如果在含有大量水的熔融KF-2 HF中进行碳电极的钝化，则用HOPG获得的图像的六方对称性丢失。(C)2001 Elsevier Science B. V.保留所有权利。
During the fluorine evolution reaction by electrolysis of molten KF-2HF, a thin solid fluoro-carbon layer is formed on carbon anodes. This film is mainly composed of fluorine-graphite intercalation compound and a small amount of insulating graphite fluorides. Impedance measurements performed in mercury and cyclic voltammetry studies in aqueous solution containing a redox couple have shown that the surface him behaves like an electronic conductor and cannot constitute a high energy barrier for the electron transfer in electrochemical reactions. However, the kinetics of the fluorine evolution reaction is strongly dependent on the water content in KF-2HF, indeed, water contributes to the formation of graphite fluorides which limit the fluorine evolution reaction. STM measurements performed on crude and passivated highly oriented pyrolitic graphite (HOPG) samples have pointed out the heterogeneities of composition of this carbon-fluorine him and the influence of water. It has been shown that, if the passivation of the carbon electrodes was performed in molten KF-2HF containing a high amount of water, the hexagonal symmetry of the images obtained with HOPG is lost. (C) 2001 Elsevier Science B.V. All rights reserved.