Studies on Suppression of Hydrogen Evolution Reaction for Zinc/Air Fuel Cell
We studied the electrochemical behavior of a zinc oxide anode in the presence of succinic acid as an organic additive. This additive was added to the electrolyte, which is 8.5 M KOH solution containing 25g of ZnO and 3000 ppm of polyethylene glycol in 1 liter of water. The modified electrolyte was newly attempted to improve the main problems namely the hydrogen overpotential and dendrite formation during cycling in Zn/Air energy system. The results obtained in the presence of succinic acid were compared with the behavior of the electrolyte 8.5 M KOH in the absence of the additive. It has been concluded that the hydrogen overpotential is raised enormously, shifting to the more negative potential side as -4.19 V vs. Hg/HgO while zinc oxide electrode was at -1.399 V. Similarly, we found that dendrite formation on the surface of zinc oxide anode is reduced to some extent by scanning electron micrographs.
T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran
C. W. Lee et al., "Studies on Suppression of Hydrogen Evolution Reaction for Zinc/Air Fuel Cell", Materials Science Forum, Vols. 539-543, pp. 1427-1430, 2007