Cathodes For Photodriven Hydrogen Generators: Znte and Cdte

ZnTe (Eg = 2.26 eV) and CdTe (Eg = 1.5 eV) were studied as possible candidates for a photocathode in the photoelectro-chemical production of hydrogen. Current-potential relationships with and without light, photocurrent-wavelength relationships at various potentials, and the flatband potential, were measured for both electrodes in 1 N NaOH solution. the stabilities of both electrodes in NaOH solution were also examined. CdTe is a possible photocathode, but ZnTe is unacceptable, because the photocurrent appears at a too-negative potential in relation to its negative flatband potential, and because of its low stability.