Surface science studies of electrochemical energy storage devices

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7234526

Wang, K

Using ultra-high-vacuum (UHV) surface and electrochemical techniques, three interfacial systems have been studied, including KOH/Ni (111), CO[sub 2]/K/Ag(111) and THF/Li interfaces, which were associated with electrochemical energy storage devices. Desorption of CO[sub 2] on K-dosed Ag(111) was investigated using temperature desorption (TPD), Auger electron (AES), x-ray photoelectron (XPS), work function measurements, and high resolution electron energy loss (HREELS) spectroscopies. The TPD spectra on CO[sub 2]-saturated K/Ag(111) exhibited a sharply defined m/e = 44 peak at 796 K with no evidence for desorption of CO at any temperature. An oligomeric CO[sub 2] chain model was proposed to explain the desorption feature. Adventitious water and oxygen in the system and/or defect sites in the Ag(111) crystal gave rise to an additional m/e = 44 peak at much higher temperature, which was attributed to the formation of ordinary carbonate. Electrochemical properties of Ni(111) prepared and characterized in UHV were examined in 0.1 M KOH by cyclic voltammetry using an UHV-electrochemistry transfer system. A saturation coverage (0.5) of CO was used to protect the Ni(111) from possible contamination during the transfer. The results indicated that the CO layer remained intact up to the moment of contact with the electrolyte and could be further electro-oxidized. Only one monolayer of Ni metal was involved in the electrochemically formed film in the first voltammetric cycle and less than two monolayers upon repeated cycling. Surfaces which were not protected by CO displayed the same behavior. The reaction of THF (tetrahydrofuran) with Li was studied. THF adsorbed on deposited Li films with partial dissociation, yielding less than a monolayer mixture of THF and dissociated products on the surface. It was observed that Li diffused into Ag above room temperature. The electron beam in AES and x-rays in XPS caused severe damage to THF.

• Research Organization: Case Western Reserve Univ., Cleveland, OH (United States)
• OSTI ID: 7234526
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
250800* -- Energy Storage-- Chemical
36 MATERIALS SCIENCE
360602 -- Other Materials-- Structure & Phase Studies
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400 -- Electrochemistry
ALKALI METAL COMPOUNDS
ALKALI METALS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
CHEMISTRY
DESORPTION
DISSOCIATION
ELECTROCHEMISTRY
ELEMENTS
ENERGY STORAGE
FILMS
FURANS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
HYDROXIDES
INTERFACES
LITHIUM
METALS
NICKEL
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
POTASSIUM COMPOUNDS
POTASSIUM HYDROXIDES
SILVER
SORPTION
STORAGE
SURFACE PROPERTIES
SURFACES
TETRAHYDROFURAN
TRANSITION ELEMENTS