ISSN:
1057-9257
Keywords:
Phosphors
;
Alkaline
;
Earth sulphides
;
Photoluminescence
;
CaS
;
SrS
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Electrical Engineering, Measurement and Control Technology
,
Physics
Notes:
Ca1 - xSrxS Solid Solutions at 10 m/o intervals have been prepared by coprecipitation of sulphates from aqueous solution followed by reduction at 1000°C with hydrogen. Phosphorescence emission spectra have been determined for these solid solutions doped with 0.1 m/o cerium and show a blue shift with increasing strontium content from 2.46 to 2.59 eV. Hyperbolic phosphorescent decay curves were observed at both room and liquid nitrogen temperatures across the composition range and have been broken down into three exponential components by graphical and computer-programme-based methods. At room temperature trap depth values of 0.366, 0.316 and 0.282 eV with measured lifetimes of 1.9, 0.26 and 0.07 ms respectively were determined with little dependence on composition. At liquid nitrogen temperature shallower traps were observed at 0.103, 0.086 and 0.076 eV with respective decay times of 5, 0.4 and 0.09 ms having little sensitivity to changes in the host compostion. These traps are related to intrinsic defects, some of which may be surface in character. The blue shift in emission peak energy with the decrease in band gap from CaS to SrS is discussed.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/amo.860030140
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