Previously, it had been shown that copper halide films grown on copper immersed in neutral solutions containing halide ions exhibited photopotential behavior.1 The reported band gap energies of the cuprous halide films were correlated with the spectral responses of the photopotentials. The sign of the photopotentials and the semiconductor type were in accord with Williams’ theory. In this study, polarization and photopotentials of zinc single crystals immersed in Na2S were measured.
The single crystals of zinc were grown in capsules made of pyrex glass tubing in an atmosphere of hydrogen. The metal was obtained from the National Bureau of Standards, Washington, DC. It was of relatively high purity (>99.99% Zn purity) and is used for melting point determinations.
The zinc single crystals as grown were approximately 1.27 cm in diameter and several cm long. The c-axis was almost parallel to the longitudinal axis of the specimen. Disk...
