Accession Number : AD0703649

Title :   THE DISSOLUTION KINETICS OF LITHIATED NICKEL OXIDE IN AQUEOUS SOLUTIONS.

Descriptive Note : Technical rept.,

Corporate Author : CASE WESTERN RESERVE UNIV CLEVELAND OHIO ELECTROCHEMISTRY RESEARCH LAB

Personal Author(s) : Lee,Chin-Ho ; Yeager,Ernest

Report Date : 01 OCT 1969

Pagination or Media Count : 149

Abstract : The dissolution kinetics of lithiated nickel oxide electrodes have been studied in aqueous acid solutions at 95C and lower temperatures at potentials from 0.26 V to 1.8 V vs SHE. The potential dependence of the dissolution rate observed at potentials anodic to about 1.3 V vs SHE fits well Vermilyea's equation indicating that the transfer of either cations or anions (depending on the potential) across a potential energy barrier is rate controlling with most of the change in applied potential appearing between the Helmholtz plane in the oxide and that in the solution. At potentials cathodic to about 1.3V, the data also fit the same equation but with a much higher Tafel slope because much of the overall potential drop is across the space charge layer in the oxide. The activation enthalpy at the flat band potential is about 23 kcal/mole. The effects of H(+) concentration and complexing agents such as EDTA have been examined. The reaction order is 1/3 to 1/2 with respect to H(+) and 1 with respect to EDTA. No dependence of the dissolution rate on the simultaneous oxidation of Tl(+) to Tl(3+) was found. Isotopic (18O) studies have indicated that at potentials anodic to about 1.8 V vs SHE lattice oxide ions are a significant source of O2 liberated anodically probably because of p-carriers falling into surface traps involving oxide ions. (Author)

Descriptors :   (*NICKEL COMPOUNDS, *ELECTRODES), (*ELECTROCHEMISTRY, *NICKEL), (*ADSORPTION, ELECTRODES), LITHIUM, OXIDES, PH FACTOR, ETHYLENEDINITRILO TETRAACETATES, COMPLEX COMPOUNDS, SOLUTIONS(MIXTURES), IONS, OXYGEN, SEMICONDUCTORS

Subject Categories : Physical Chemistry
      Energy Storage

Distribution Statement : APPROVED FOR PUBLIC RELEASE