Effect of Sulfate Acid on Electrolysis Process for Preparing EMD Using an Oxygen Depolarized Cathode

• Main Authors: Hui ZHANG, Huimin MENG
• Format: Article
• Language: English
• Published: IFSA Publishing, S.L. 2014-04-01
• Series: Sensors & Transducers
• Subjects: Gas diffusion electrode; Electrolytic manganese dioxide; Sulfuric acid; Electro-catalytic activity; Stability.
• Online Access: http://www.sensorsportal.com/HTML/DIGEST/april_2014/Vol_169/P_RP_0101.pdf

Electrolytic manganese dioxide (EMD) was prepared by using gas diffusion electrode (GDE) instead of traditional hydrogen evolution cathode. Sulfate acid’s effects on the cell voltage, the current efficiency, the electro-catalytic activity and the lifetime of GDE are studied. The results show that as the concentration of sulfuric acid increases, the current efficiency increases, while the cell voltage and the lifetime of GDE decreases. When the concentration of sulfuric acid is 20-40 g·dm- 3, the cell voltage is 1.1-1.2 V and the current efficiency is more than 99 %. When the concentration of sulfuric acid is 30 g·dm-3, the GDE has the best electro-catalytic activity, meanwhile the cell voltage maintains at 1.6 V after EMD is deposited on anode, and the lifetime of GDE reaches 400 h. XRD patterns show that all of the electrolytic products belong to g-MnO2 in different sulfuric acid concentration.