Free Access
Volume 27, Number 10, December 1999
Page(s) 839 - 846
Section Original articles
Analusis 27, 839-846 (1999)
DOI: 10.1051/analusis:1999151

Determination of silver in layered monocrystals of thermoelectric tellurides by graphite furnace atomic absorption spectrometry

J. Srámková, S. Kotrlý and M. Peknicová

Department of Analytical Chemistry, University of Pardubice, 532 10 Pardubice, Czech Republic

(Received June 15, 1999; revised December 12, 1999; accepted December 14, 1999.)

Critical assessment of the processes affecting the atomization of silver in graphite tube helped to develop a precise and reliable method applicable for interpretation of the silver content in telluride materials in relation to their thermoelectric coefficients. While milligram samples of bismuth telluride were easily dissolved in dilute nitric acid, for samples of bismuth antimony telluride an addition of hydrochloric acid was necessary. Tartaric acid was then added, not only to prevent hydrolysis but also to serve as a chemical modifier in graphite furnace AAS determination of Ag at 328.1 nm. Over the range of 0.5 to 7.5 ng ml-1 of Ag the linear calibrations were obtained with a good and long-run reproducibility. A $3\sigma$ limit of detection for $20~\mu$l aliquots was of the order of 0.1 ng ml-1.

Key words: Determination of silver / bismuth antimony telluride / thermoelectric material / atomic absorption spectrometry / graphite furnace / matrix modifier.

© EDP Sciences, Wiley-VCH 1999