Photoelectrochemical cells based on GaAs0.6P0.4 epilayers: Stabilization and luminescent properties

Stable, efficient photoelectrochemical cells (PEC’s) have been constructed from an n-type material used in light-emitting diode (LED) fabrication. The photoelectrode, which consists of an epilayer of GaAs0.6P0.4 on a graded layer terminating in a GaAs substrate, can be used in a PEC employing aqueous ditelluride electrolyte to convert 457.9-nm light to electrical energy with efficiencies which routinely exceed 16% at incident intensities of ∼10 mW/cm2. Photoluminescence from these electrodes can be substantially quenched by the passage of photoanodic current during PEC operation.