Photoluminescent Properties of n-GaAs Electrodes: Simultaneous Determination of Depletion Widths and Surface Hole-Capture Velocities in Photoelectrochemical Cells.
WISCONSIN UNIV-MADISON DEPT OF CHEMISTRY
Pagination or Media Count:
Steady-state photoluminescence measurements performed on n-GaAs electrodes used in photoelectrochemical cells PECs employing a stabilizing, aqueous telluride electrolyte yield values for the electrodes depletion width W and surface hole-capture velocity S. Between -1.0 V a potential near short circuit and -1.5 V vs. an SCE reference electrode a potential near open circuit at the photon flux of 1 x 10 to the 15th power photonssq cm employed, the interface behaves ideally virtually all of the applied potential appears in the semi-conductor space-charge region. Over this potential regime S is determined to be constant to within 10 and has a value, using literature values for hole lifetime and diffusion length, of approximately 200,000 cms for n-GaAs electrodes having carrier concentrations of 1 - 4 x 10 to the 17th powercu cm. Similar values of S obtained in air and in the PEC suggest a common rate-limiting mechanism for hole consumption in the two media.
- *PHOTOELECTRIC CELLS(SEMICONDUCTOR)
- STEADY STATE
- PHOTOCHEMICAL REACTIONS
- GALLIUM ARSENIDES
- CHARGE CARRIERS
- HOLES(ELECTRON DEFICIENCIES)
- SHORT CIRCUITS
- SPACE CHARGE
- Electrical and Electronic Equipment