Photoelectrolysis of water for production of hydrogen. Final report, 1 March 1979-8 March 1981

Technical Report · Tue Sep 01 04:00:00 EDT 1981

OSTI ID:5952309

No single chemical compound meets all the requirements for catalytic electrodes to be used in photoelectrolysis. Three different approaches toward the development of materials for such electrodes have been investigated. Composite structures have been prepared by depositing sputtered CdSe-SrTiO/sub 3/ and CdSe-TiO/sub 2/ films on CdSe substrates; solid solutions of TiO/sub 2/ with oxides of Ta, W, Nb, V and Mo and of SrTiO/sub 3/ with LaFeO/sub 3/, SrVO/sub 3/ and SrMoO/sub 3/ have been prepared, primarily by ceramic techniques; and CdSe and SrTiO/sub 3/ surfaces have been modified by Ar-ion bombardment. These three approaches were evaluated by fabricating electrodes from materials prepared by each method and then characterizing and testing these electrodes, mainly by measuring current-voltage characteristics, spectral response and chemical stability during their operation in electrochemical cells. None of the three approaches investigated has produced efficient photoelectrolysis electrodes. One of the problems encountered in fabricating composite electrodes is that the CdSe substrates cannot be heated high enough to reduce the sputtered SrTiO/sub 3/ or TiO/sub 2/ without causing decomposition of the CdSe. Of the two types of composite electrodes investigated, those with CdSe-TiO/sub 2/ films have produced higher photocurrents, within an order of magnitude of those of bare CdSe, but they are photoelectrochemically unstable. For some of the TiO/sub 2/ and SrTiO/sub 3/ alloys that have been investigated the photoresponse shifts to lower energies as desired, but the magnitude of the response is drastically decreased and the speed of the response to visible light is slow, suggestive of deep traps or recombination centers. Surface modification of CdSe by Ar-ion bombardment has produced only deleterious effects, namely lowering of the photocurrent and sharpening of the response spectrum, without any marked increase in photoelectrochemical stability.

• Research Organization: Solar Energy Research Inst., Golden, CO (USA); Massachusetts Inst. of Tech., Lexington (USA). Lincoln Lab.
• DOE Contract Number: AC02-77CH00178
• OSTI ID: 5952309
• Report Number(s): SERI/TR-91358; ON: DE82003097
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
080101* -- Hydrogen-- Production-- Electrolysis
14 SOLAR ENERGY
140505 -- Solar Energy Conversion-- Photochemical
Photobiological
& Thermochemical Conversion-- (1980-)
ALKALINE EARTH METAL COMPOUNDS
ANODES
ARGON IONS
BAND THEORY
CADMIUM COMPOUNDS
CADMIUM SELENIDES
CHALCOGENIDES
CHARGED PARTICLES
COMPOSITE MATERIALS
CURRENTS
DISPERSIONS
ELECTRIC CURRENTS
ELECTRIC POTENTIAL
ELECTROCHEMICAL CELLS
ELECTRODES
ELECTROLYSIS
ELECTROLYTIC CELLS
ENERGY LEVELS
EQUIPMENT
FABRICATION
HYDROGEN PRODUCTION
IONS
LYSIS
MATERIALS
MIXTURES
OXIDES
OXYGEN COMPOUNDS
PHOTOANODES
PHOTOELECTROCHEMICAL CELLS
PHOTOELECTROLYSIS
PHOTOELECTROLYTIC CELLS
RECOMBINATION
SELENIDES
SELENIUM COMPOUNDS
SEMICONDUCTOR MATERIALS
SOLAR EQUIPMENT
SOLID SOLUTIONS
SOLUTIONS
SPECTRAL RESPONSE
SPUTTERING
STABILITY
STRONTIUM COMPOUNDS
STRONTIUM OXIDES
SURFACE TREATMENTS
TEMPERATURE EFFECTS
TESTING
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
TRAPS