потенциал

DOI: https://doi.org/10.18500/1608-4039-2017-17-3-143-158

УДК 541.135

DOI: https://doi.org/10.18500/1608-4039-2016-16-2-47-61

Electrochemical activity of electrodes for electrolysis of water is investigated. As catalysts coating Ni-S-Co, suspension LaNi_2.5Co_2.4Al_0.1 or their combinations were applied. As electrolyte at test of electrodes 30% KOH or NaOH is used. Current density varied in a range from 10 to 600 мА/cm² at temperature 20-80°C. When the temperature increases from 20 to 80°C the current density on cathodes with composite LaNi2.5Co2.4Alo.i/Ni-S-Co catalyst increases 4 times at constant potential E = –1.10 V (rel. Hg/HgO). When the current density of more than 100 mA/cm² cathodes with all catalysts offered by us in this work have lower value of potential than the similar cathodes described in the scientific literature. In contrast to the cathodes, catalyst LaNi_2.5Co_2.4Al_0.1/Ni–S–Co does not render influence on electrochemical activity of the anode.

Electrochemical activity of anodes on the basis of a nickel mesh grid for water electrolysis is investigated. Activation of anodes was made by three ways:
1) chemical covering sulfur-containing compounds of nickel and iron;
2) immersing in solution Na₂S₂O₃ + H₂SO₄ (till pH=3);
3) immersing in solution Na₂S + H₂SO₄ (till pH=3).
The water solution 6M KOH was used as the electrolyte while the electrodes testing. Current density varied in a range from 1 to 600 mAJ cm2 at temperature 20, 50 and 70°C. The greatest electrochemical activity have anodes activated by the third method. The anode potential at current density 600 mA/cm² and temperature 70°C is equal +0.57 V (concerning Hg/HgO – the comparison electrode).