Electrolytic cathode structure and electrolyzer using the same
Provided are an electrolytic cathode structure that can suppress the degradation of an activated cathode even if a reverse current flows upon the stoppage of operation of an electrolyzer in an electrode structure allowing the distance between the electrode and an electrode current collector to be maintained at an approximately constant value, and an electrolyzer using the same. The electrolytic cathode structure includes a metal elastic cushion member 1 compressed and accommodated between an activated cathode 2 and a cathode current collector 3 . At least a surface layer of the cathode current collector 3 consumes a larger oxidation current per unit area than the activated cathode. The electrolyzer is partitioned by an ion exchange membrane into an anode chamber for accommodating an anode and a cathode chamber for accommodating a cathode. The electrolytic cathode structure is used for the cathode.
1. An electrolytic cathode structure in which a metal elastic cushion member is compressed and accommodated between an activated cathode and a cathode current collector, where
a surface layer of the cathode current collector includes a material that consumes more than 0.08 F/m 2 oxidation current at lower than 0v vs. Hg—HgO potential in an alkaline solution, wherein at least the surface layer of the cathode current collector is made of activated carbon-nickel composite plating,
and wherein at least a surface layer of the cathode current collector consumes a larger oxidation current per unit area than the activated cathode.
2. The electrolytic cathode structure according to claim 1 , wherein the activated cathode is a pyrolytic activated cathode selected from a group consisting of Ru—La—Pt based, Ru—Ce based, Pt—Ce based and Pt—Ni based cathodes.
3. The electrolytic cathode structure according to claim 1 , wherein the metal elastic cushion member is a metal coil cushion.
4. The electrolytic cathode structure according to claim 3 , wherein the metal elastic cushion member is an elastic cushion member formed by twisting a metal coil around an anticorrosive frame.
5. The electrolytic cathode structure according to claim 1 , the activated cathode is a pyrolytic activated cathode selected from a group consisting of Ru—La—Pt based, Ru—Ce based, Pt—Ce based and Pt—Ni based cathodes, and the metal elastic cushion member is an elastic cushion member formed by twisting a metal coil around an anticorrosive frame.
6. An electrolyzer partitioned by an ion exchange membrane into an anode chamber for accommodating an anode and a cathode chamber for accommodating a cathode, the electrolyzer being characterized in that the electrolytic cathode structure according to claim 1 is used for the cathode.
7. The electrolytic cathode structure according to claim 1 , wherein the surface layer of the cathode current collector is easier to oxidize than the activated cathode, and the surface layer of the cathode current collector has a surface area that allows the cathode current collector to consume a larger oxidation current per unit area than the activated cathode.
8. An electrolytic cathode structure in which a metal elastic cushion member is compressed and accommodated between an activated cathode and a cathode current collector, where
a surface layer of the cathode current collector includes a material that consumes more than 0.08 F/m 2 oxidation current at lower than 0v vs. Hg—HgO potential in an alkaline solution,
wherein at least the surface layer of the cathode current collector is made of a metal of hydrogen absorbing alloy-based dispersion plating,
and wherein at least a surface layer of the cathode current collector consumes a larger oxidation current per unit area than the activated cathode.