Accession Number:

ADA183343

Title:

Investigations at the n-HfS2/Non-Aqueous Electrolyte Interfacial Region.

Descriptive Note:

Technical rept. Oct 86-Jul 87,

Corporate Author:

ELTRON RESEARCH INC AURORA IL

Personal Author(s):

• Semkow,Krystyna W.
• Pujare,Nirupama U.
• Sammells,Anthony F.

Report Date:

1987-07-01

Pagination or Media Count:

27.0

Abstract:

Single crystal n-Hafnium disulfide photoelectrodes prepared by halogen vapor transport were investigated in 0.1M TBAPF 6Acetonitrile electrolyte using both impedance and admittance spectroscopy techniques. The presence of frequency dependent capacitive and resistive elements in the equivalent circuit for n-Hfs2electrolyte interface were evident. Measured capacitance effects at the interfacial region were found dependent upon the crystal orientation used, with that for defect free van der Waals surfaces being 10 to the 8th powersq. cm. and order of magnitude lower than for n-HfS2 intercalation layers exposed to the electrolyte. High capacitance values were correlated with a high population of surface charges. Admittance spectroscopy analysis suggested the presence of surface states associated with surface adsorption processes. Open-circuit photovoltages up to 0.35V under 100mWsq. cm illumination were observed for van der Waals surfaces, decreasing to 0.16V as the population intercalating layers exposed to the electrolyte was increased.

Descriptors:

• *ELECTROLYTES
• ADMITTANCE
• ADSORPTION
• CAPACITANCE
• CIRCUITS
• CRYSTALS
• ELECTROLYTES
• EQUIVALENT CIRCUITS
• EXPOSURE(GENERAL)
• HALOGENS
• ILLUMINATION
• INTERFACES
• ORIENTATION(DIRECTION)
• PHOTOVOLTAIC EFFECT
• POPULATION
• SPECTROSCOPY
• SURFACE PROPERTIES
• SURFACES
• TRANSPORT
• VAPORS
• HAFNIUM COMPOUNDS

Subject Categories:

• Inorganic Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE