Photoelectrolysis of water in sunlight with sensitized semiconductor electrodes

Journal Article · Sat Oct 01 04:00:00 EDT 1977 · J. Electrochem. Soc.; (United States)

DOI:https://doi.org/10.1149/1.2133104· OSTI ID:5076736

Ghosh, A K; Maruska, H P

In all previous studies of the photoelectrolysis of water, very little attention has been paid to the carrier generation and transport properties of the optically active semiconductor electrode. To gather such information the present work theoretically analyzes the spectral response of TiO/sub 2/ photoelectrolysis cells. Comparison with experimental results allows us to determine the diffusion length of minority carriers in TiO/sub 2/ for the first time. It is the hole transport that governs the spectral response curve, not the electron transport. The quantum efficiency of carrier generation in TiO/sub 2/ electrodes in the photolysis mode can be increased to 80% by doping the crystals with Al. The sunlight conversion efficiency has been raised to 1.3% from 0.4% reported earlier by others. The spectral response of the device has been extended into the visible portion of the spectrum through sensitization of the TiO/sub 2/ with Cr dopant impurities, allowing hydrogen generation with visible light. The photoelectrolytic processes associated with the impurity doped crystals are discussed. 36 references.

• Research Organization: Exxon Research and Engineering Co., Linden, NJ
• OSTI ID: 5076736
• Journal Information: J. Electrochem. Soc.; (United States), Journal Name: J. Electrochem. Soc.; (United States) Vol. 124:10; ISSN JESOA
• 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-)
ALLOYS
CHALCOGENIDES
CHARGE CARRIERS
CHARGE TRANSPORT
CHROMIUM ADDITIONS
CHROMIUM ALLOYS
CONVERSION
CRYSTAL DOPING
DIFFUSION LENGTH
EFFICIENCY
ELECTRODES
ELECTROLYSIS
ELECTROLYTIC CELLS
ENERGY CONVERSION
HOLES
HYDROGEN COMPOUNDS
HYDROGEN PRODUCTION
LYSIS
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTROLYSIS
PHOTOELECTROLYTIC CELLS
REAGENTS
SEMICONDUCTOR MATERIALS
SENSITIZERS
SOLAR ENERGY CONVERSION
SPECTRAL RESPONSE
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
WATER