Original scientific paper
Diffuse reflectance of CdO
Badr S. Farag
; Department of Physics, National Research Centre, Cairo, Egypt
Aziza M. Abou El-Soud
; Department of Physics, National Research Centre, Cairo, Egypt
Abstract
The diffuse reflectance of different samples of CdO prepared from CdCO3 by firing at different temperatures from 400 and up to 1000°C was measured at room temperature in the wavelength range from 400 to 1500 nm. The energy gap or these different samples were then deduced as well as the position and number of the indirect transitions which were found to be dependent on the firing temperature. So we conclude that for firing temperatures less than 600°C Cd interstitials are present, while for firing temperatures greater than 700°C oxygen vacancies are the predominant. The more stoichiometric CdO may be prepared by firing CdCO3 between 600 and 700°C, for which the energy gap is 2.3 eV with one indirect transition appearing at 1.2 eV gap.
Keywords
Hrčak ID:
331135
URI
Publication date:
2.12.1986.
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