标题: Decoupling water electrolysis by a liquid metal electrolyzer

作者: Li, WM (Li, Wenmiao); Shi, H (Shi, Hao); Du, KF (Du, Kaifa); Chen, D (Chen, Di); Guo, L (Guo, Lei); Pang, FZ (Pang, Fangzhao); Guo, L (Guo, Lei); Liu, MH (Liu, Minghao); Li, XY (Li, Xinyu); Fang, ZY (Fang, Zhouyu); Wang, DH (Wang, Dihua); Yin, HY (Yin, Huayi)

来源出版物: CHEMICAL ENGINEERING JOURNAL  卷: 518  文献号: 164469  DOI: 10.1016/j.cej.2025.164469  Published Date: 2025 AUG 15  

摘要: Electrolytic hydrogen (e-H-2) produced by water electrolysis is a clean energy carrier, which can be directly used as a fuel or converted back to electricity. A simple electrolyzer and a suitable mediator are the key to decoupling water electrolysis, by which the costly membranes and catalysts are avoided. Herein, we build a decoupled water electrolyzer that consists of a liquid metal cathode, a molten hydroxide electrolyte, and a cheap nickel oxygen-evolution anode. The first step is to convent NaOH to liquid NaBi alloy at the cathode and oxygen and water at the Ni anode. The second step is to produce H-2 and regenerate NaOH and Bi by the reaction of the liquid NaBi and water. The two steps take place at the same reactor and the net reaction is to break water into oxygen and hydrogen. The use of liquid Bi shifts the Na deposition potential similar to 0.7 V to the positive direction and prevents Na floating, suppressing the competing hydrogen evolution reaction and avoiding the membrane. A dense and thin (similar to 1.5 mu m) protective NiO layer makes the Ni anode work stably over 100 h. The energy consumption is 46.4 Wh/mol-Na (in liquid NaBi alloy) at 50 mA/cm(2), which equals to 92.8 Wh/mol-H-2. In addition to hydrogen production, the electricity-to-liquid metal-to-hydrogen conversion process can be aligned with fluctuation of renewable energy to achieve both energy storage and hydrogen production.

作者关键词: Decoupling water electrolysis; Liquid metal electrode; Hydrogen; Molten salt electrolysis

KeyWords Plus: MEMBRANE ELECTROLYZERS; HYDROGEN-PRODUCTION; OXYGEN EVOLUTION; ENERGY; GENERATION; HYDROLYSIS; OXIDATION; ALUMINUM; SOLAR; H-2

地址: [Li, Wenmiao; Shi, Hao; Du, Kaifa; Chen, Di; Guo, Lei; Pang, Fangzhao; Guo, Lei; Liu, Minghao; Li, Xinyu; Fang, Zhouyu; Wang, Dihua; Yin, Huayi] Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430072, Peoples R China.

[Li, Wenmiao; Shi, Hao; Du, Kaifa; Chen, Di; Guo, Lei; Pang, Fangzhao; Guo, Lei; Liu, Minghao; Li, Xinyu; Fang, Zhouyu; Wang, Dihua; Yin, Huayi] Wuhan Univ, Int Cooperat Base Sustainable Utilizat Resources &, Wuhan 430072, Peoples R China.

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

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

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

Wang, DH (通讯作者)，Wuhan Univ, State Key Lab Water Resources Hydropower Engn Sci, Wuhan 430072, Peoples R China.

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

影响因子：13.2