title: Comparison of the oxygen reduction reaction between NaOH and KOH solutions on a Pt electrode: the electrolyte-dependent effect.
abstract: The oxygen reduction reaction (ORR) on a polycrystalline Pt surface was studied using cyclic voltammetry techniques, and the influence of reaction media on the ORR is examined by comparing the ORR in NaOH and KOH solutions with concentration ranging from 0.5 to 14 M at 298 K. The results show that, in NaOH and KOH solutions, the ORR, a quasi-reversible diffusion-controlled reaction, is largely dependent on the electrolyte conditions, and KOH solutions are superior to NaOH solutions for the ORR process in both thermodynamic and kinetic consideration. As the alkaline concentration increases, the ORR performance frustrates, and the protonation of superoxide is suppressed; thus, the ORR shifts from a 2e reduction pathway to a 1e reduction pathway in both solutions.
authors.affiliation: National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Jin
authors.forename: Hao
authors.initials: H
authors.lastname: Du
authors.forename: Shili
authors.initials: S
authors.lastname: Zheng
authors.forename: Hongbin
authors.initials: H
authors.lastname: Xu
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D004058:Diffusion; D004566:Electrodes; D004573:Electrolytes / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry*; D007700:Kinetics; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*; D012972:Sodium Hydroxide / Q000737:chemistry*; D013696:Temperature; D013816:Thermodynamics
chemical_list: D004573:Electrolytes; D006878:Hydroxides; D017680:Potassium Compounds; D010984:Platinum; D012972:Sodium Hydroxide; D010100:Oxygen; C029943:potassium hydroxide