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

Technical Report · Mon Oct 20 04:00:00 EDT 1980

OSTI ID:6506299

Noufi, R; Tench, D; Warren, L

The overall goal of this program is to provide the basis for designing a practical photoelectrochemical cell based on the II-VI compound semiconductors. Emphasis is on developing new electrolyte redox systems 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. Work on redox couple stabilization of n-CdX photoanodes was focused on fast one-electron couples, including Fe(EDTA)/sup 1/sup -//2/sup -//, Co(bipy)/sup 3/sup +//2/sup +//, Fe(CN)/sub 4/(bipy)/sup 1/sup -//2/sup -//, and the chloro-complexes of iron and copper, in various nonaqueous solvents. This represents an extension of our work with the methanol/ferro-ferricyanide system, which, although stabilizing for n-CdSe photoanodes, has been found to be photolytically unstable. Very promixing results were obatined for the alkylammonium chloro-Fe(II,III) couple in acetonitrile. Conducting polymer films of polypyrrole photoelectrochemically deposited onto n-type semiconductors have been shown to protect these electrode materials from photodecomposition while permitting electron exchange with the electrolyte. Good performance characteristics were attained in some cases, although observed dark currents were often appreciable.In a basic aqueous ferro-ferricyanide electrolyte containing cyanide ion, the measured open circuit voltage for n-CdTe was 1.3 V, which is practically the bandgap for this material - a notable result. Although the electrode reaction in this case involves irreversible CN/sup -/ oxidation and peeling is presently a problem with polypyrrole films on semiconductor photoanodes, such data provide considerable encouragement and incentive for the further development of photoelectrochemical cells.

• Research Organization: Rockwell International Corp., Thousand Oaks, CA (USA)
• DOE Contract Number: AC02-77CH00178
• OSTI ID: 6506299
• Report Number(s): SERI/TR-9276-T4; ON: DE83006267
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140505* -- Solar Energy Conversion-- Photochemical
Photobiological
& Thermochemical Conversion-- (1980-)
ACETONITRILE
ALCOHOLS
AMINO ACIDS
ANODES
ARSENIC COMPOUNDS
ARSENIDES
AZINES
BIPYRIDINES
CADMIUM COMPOUNDS
CADMIUM SELENIDES
CARBOXYLIC ACIDS
CHALCOGENIDES
CHELATING AGENTS
COBALT COMPOUNDS
COMPLEXES
CURRENTS
DATA
EDTA
ELECTRIC CURRENTS
ELECTROCHEMICAL CELLS
ELECTRODES
ELECTROLYTES
EQUIPMENT
EXPERIMENTAL DATA
FERRICYANIDES
FERROCYANIDES
GALLIUM ARSENIDES
GALLIUM COMPOUNDS
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
INFORMATION
IRON COMPLEXES
IRON COMPOUNDS
METHANOL
NITRILES
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOTOANODES
PHOTOCURRENTS
PHOTOELECTROCHEMICAL CELLS
PNICTIDES
PYRIDINES
SELENIDES
SELENIUM COMPOUNDS
SOLAR EQUIPMENT
STABILIZATION
TRANSITION ELEMENT COMPLEXES
TRANSITION ELEMENT COMPOUNDS
VOLTAMETRY