标题：Unusual temperature effect on the stability of nickel anodes in molten carbonates

作者：Du, KF (Du, Kaifa); Zheng, KY (Zheng, Kaiyuan); Chen, ZG (Chen, Zhigang); Zhu, H (Zhu, Hua); Gan, FX (Gan, Fuxing); Wang, DH (Wang, Dihua)

来源出版物：ELECTROCHIMICA ACTA卷：245页码：402-408 DOI：10.1016/j.electacta.2017.05.149 出版年：AUG 10 2017

摘要：The stability of nickel anode in a eutectic molten Li2CO3-Na2CO3-K2CO3 electrolysis cell was systematically investigated over the temperature range of 450 degrees C to 750 degrees C. An unusual temperature effect was observed involving a critical activation- passivation transition temperature at 575 degrees C for the nickel in the melt; rapid dissolution of nickel was found to occur below 575 degrees C under anodic polarization, whereas its surface became passivated above this temperature, and the stability of the passivation film was further improved by increasing the temperature up to 750 degrees C. A blackish oxide film forms on nickel surfaces that retard the anodic dissolution of nickel. The composition and structure of the oxide film, as well as its formation mechanism, were studied by electrochemical measurements combined with X- ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) characterization. Two temperature sensitive oxidation states of nickel (i.e., Ni(II) and Ni(III)) formed during the anodic polarization. Ni( III) tended to combine with Li2CO3 to form the more soluble LiNiO2 during anodic polarization at lower temperature, and its content in the film decreased dramatically with increasing temperature. Thus, a stable and protective film consisting of NiO can form at temperatures above 575 degrees C.

入藏号：WOS:000406762700044

文献类型：Article

语种：English

作者关键词： Nickel; Electrochemistry; Anodization; Oxidation; Oxide-film composition; Temperature effect

扩展关键词： INERT ANODE; ELECTROCHEMICAL CHARACTERIZATION; CATHODE MATERIAL; BEHAVIOR; OXYGEN; NIO; ELECTROLYSIS; SUPERALLOYS; OXIDE; CELL

通讯作者地址：Wang, DH (通讯作者),Wuhan Univ, Sch Resource & Environm Sci, Int Cooperat Base Sustainable Utilizat Resources, Wuhan 430072, Hubei, Peoples R China.

电子邮件地址：wangdh@whu.edu.cn

地址： [Du, Kaifa; Zheng, Kaiyuan; Chen, Zhigang; Zhu, Hua; Gan, Fuxing; Wang, Dihua] Wuhan Univ, Sch Resource & Environm Sci, Int Cooperat Base Sustainable Utilizat Resources, Wuhan 430072, Hubei, Peoples R China.

研究方向：Electrochemistry

ISSN：0013-4686

eISSN: 1873-3859

影响因子：4.798