Mechanisms of photoluminescence at cds polycrystalline electrodes in contact with aqueous electrolytes

✍ Scribed by I.J. Ferrer; P. Salvador

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 467 KB
• Volume: 142
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(87)85131-x

✦ Synopsis

The red and infrared emissions in the photoluminescence spectra of polycrystalline CdS electrodes have been studied as a function ofthe atmosphere and temperature of annealing, excitation light intensity, applied bias and electrolyte composition. The experimental results suggest that the red luminescence is associated with a recombination mechanism involving valence band holes and electrons trapped at sulfur vacancies at about 0.7 eV below the conduction band edge. Infrared emission seems to involve, besides sulfur vacancies, cadmium vacancies (hole traps) at about 0.3 eV above the valence band edge. Both hole injection rate and concentration of S and Cd vacancies are the parameters determining the shape of the luminescence spectra.