The photoelectrochemical properties of novel GaAs/AlGaAs superlattice electrodes were investigated in nonaqueous solutions containing reversible and irreversible redox couples. The superlattice materials consisted of 35 alternating layers of 17 A Al0.35Ga0.65As and 150 Angstrom GaAs grown onto a highly doped p-GaAs substrate. Under illumination, the superlattice electrodes exhibited current/potential curves with hysteresis in decamethylferrocene(+/0) solutions. The hysteresis was due to photoinduced dark current associated with hole injection into the valence band of the semiconductor. More reducing couples such as cobaltocene(+/0) and dicarbomethoxycobaltocene(+/0) afforded stable current/potential curves with the superlattice electrodes. The irreversible homogeneous and electrochemical reduction of a series of vicinal dibromides was investigated in order to develop a redox system capable of detecting hot electron reactions.