Electrochemical photovoltaic cells/stabilization and optimization of II-VI semiconductors. Final technical report

Technical Report · Thu May 01 04:00:00 EDT 1980

OSTI ID:5113030

Noufi, R; Tench, D; Warren, L

The overall goal of this program is to provide the basis for designing a practical electrochemical solar cell based on the II-VI compound semiconductors. Emphasis is on developing new electrolyte redox sytems and electrode surface modifications which will stabilize the II-VI compounds against photodissolution without seriously degrading the long-term solar response. The bulk electrode material properties are also being optimized to provide the maximum solar conversion efficiency and greatest inherent electrode stability. Stabilization of n-CdSe against photodissolution has been achieved for the methanol/tetraethylammonium ferro-ferricyanide system. No degradation of the photocurrent or the electrode surface, even in the presence of traces of water, has been observed for runs up to 700 h at 6 mA/cm/sup 2/ and approx. AM1 light intensity. With higher quality single crystal CdSe, stable sort-circuit photocurrents of 15 to 17 mA/cm/sup 2/ and an open circuit voltage of 0.7 V (tungsten-halogen illumination) have been obtained, corresponding to a conversion efficiency of about 5%. Preliminary evaluation of a series of sulfur-containing 1,2-dithiolene metal complexes for stabilization of CdX photoanodes in acetonitrile solution has been completed. For the first time, a conducting polymer film (derived from pyrrole) has been electrochemically deposited on a semiconductor electrode. This could represent a breakthrough in the use of hydrophobic films to protect semiconductor photoanodes from dissolution/degradation. Mixed CdSe-CdTe solid solution electrodes were found to exhibit a minimum in both the flatband potential and the bandgap at approx. 65% CdTe. Both of these shifts would have a detrimental effect on the solar conversion efficiency.

• Research Organization: Rockwell International Corp., Thousand Oaks, CA (USA)
• DOE Contract Number: AC02-77CH00178
• OSTI ID: 5113030
• Report Number(s): SERI/TR-8002-T1
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140505* -- Solar Energy Conversion-- Photochemical
Photobiological
& Thermochemical Conversion-- (1980-)
ADDITIVES
ALCOHOLS
ANODES
CADMIUM COMPOUNDS
CADMIUM SELENIDES
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
CHEMISTRY
COMPLEXES
CURRENTS
DATA
DATA FORMS
DEPOSITION
DESIGN
DISSOLUTION
EFFICIENCY
ELECTRIC CURRENTS
ELECTRIC POTENTIAL
ELECTRICAL PROPERTIES
ELECTROCHEMICAL CELLS
ELECTROCHEMISTRY
ELECTRODEPOSITION
ELECTRODES
ELECTROLYSIS
ELECTROLYTES
EQUIPMENT
EXPERIMENTAL DATA
FERRICYANIDES
FERROCYANIDES
FILMS
GRAPHS
HYDROXY COMPOUNDS
INFORMATION
IRON COMPLEXES
LYSIS
MATERIALS
METHANOL
NUMERICAL DATA
OPTIMIZATION
ORGANIC COMPOUNDS
PHOTOANODES
PHOTOELECTROCHEMICAL CELLS
PHYSICAL PROPERTIES
POLYMERS
QUANTITY RATIO
REDOX REACTIONS
RESEARCH PROGRAMS
SELENIDES
SELENIUM COMPOUNDS
SEMICONDUCTOR MATERIALS
SOLAR EQUIPMENT
STABILIZATION
SURFACE COATING
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
VOLTAMETRY