1976 Volume 25 Issue 274 Pages 619-622
The CdS precipitates were prepared from aqueous solutions of cadmium chloride, bromide, nitrate, sulphate or acetate, and the relation between crystal structure and photoconductivity of these CdS precipitates was investigated. All CdS precipitates were found to be a mixture of hexagonal and cubic phases, and their mean particle sizes were about 1.5 to 4μm. All precipitates were found by chemical analysis to be slightly sulphur-rich.
Using an interdigital electrode, the spectral response of photoconductivity and the rise and decay of photocurrent were measured. All specimens showed photoconductive response in the visible wavelength region, but the peak wavelength scattered in the wavelength region of 550∼570 nm from one specimen to another. The rise or decay time was very long for the specimens prepared from cadmium chloride and bromide. The specimen prepared from cadmium sulphate had the highest photoconductive sensitivity, while the one from cadmium bromide had the lowest sensitivity.