标题: Corrosion Behavior and Mechanism of Nickel as a Hydrogen Evolution Electrode Under High Alkalinity and Temperature

作者: Wei, QY (Wei, Qinyi); Tang, MY (Tang, Mengyi); Shi, H (Shi, Hao); Zhu, H (Zhu, Hua); Du, KF (Du, Kaifa); Wang, DH (Wang, Dihua)

来源出版物: JOURNAL OF THE ELECTROCHEMICAL SOCIETY 卷: 171 期: 12 文献号: 121505 DOI: 10.1149/1945-7111/ad9d82 Published Date: 2024 DEC 3

摘要: This study investigates the hydrogen evolution on nickel (Ni) electrode in KOH-H2O system at 160 degrees C, focusing on the electrode's morphology and performance changes under cathodic polarization. At a current density of 10 mA cm-2, electrolysis voltage decreases with increasing temperature and electrolyte concentration, from 2.03 V in 1 M KOH at 25 degrees C to 1.81 V in 30 wt% KOH at 80 degrees C, and further to 1.59 V in 85 wt% KOH at 160 degrees C, respectively. In parallel, the corrosion rate increases from 0.008 mm y-1 to 0.023 mm y-1, and reaches a peak of 0.096 mm y-1 under a current density of 200 mA cm-2, respectively. The onset potential for cathodic corrosion shifts positively from -1.8 V vs Pt in 30 wt% KOH at 80 degrees C to -1.7 V in 85 wt% KOH at 160 degrees C. Preferential corrosion occurs at the surface imperfections, such as defects, scratches, and cavities. Cathodic corrosion results in the refinement of surface grains on the Ni electrode, increasing the electrochemical active surface area. However, this process concurrently reduces the efficacy of the catalyst for hydrogen evolution due to the preferential exposure of the low-energy Ni(111) crystalline facets.

作者关键词: nickel electrode; hydrogen evolution reaction; cathodic corrosion; electrocatalysis

KeyWords Plus: CATHODIC CORROSION; DEGREES-C; PRESSURE

地址: [Wei, Qinyi; Tang, Mengyi; Shi, Hao; Zhu, Hua; Du, Kaifa; Wang, Dihua] Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

[Wei, Qinyi; Tang, Mengyi; Shi, Hao; Zhu, Hua; Du, Kaifa; Wang, Dihua] Wuhan Univ, Int Cooperat Base Sustainable Utilizat Resources &, Wuhan 430072, Peoples R China.

[Wang, Dihua] Wuhan Univ, State Key Lab Water Resources Engn & Management, Wuhan 430072, Peoples R China.

通讯作者地址: Du, KF (通讯作者)，Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

Du, KF (通讯作者)，Wuhan Univ, Int Cooperat Base Sustainable Utilizat Resources &, Wuhan 430072, Peoples R China.

电子邮件地址: dukf@whu.edu.cn; wangdh@whu.edu.cn

影响因子：3.1