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

Abstract

Abstract. 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 3σ limit of detection for 20 µl aliquots was of the order of 0.1 ng ml -1 .

Analytical application of poly(vinyl chloride-co-vinyl acetate) electrode modified with silver for chloride ions determination in real systems

“…Therefore, there is a need for a fast, sensitive and simple method of determining small amounts of silver ions in different samples. There are different sensitive methods for the determination of silver ions at low levels, such as spectrophotometry (El-Zawawy et al, 1995;Ohshita et al, 1982), atomic absorption spectrometry (Bermejo-Barrera et al, 1996;Chakrapni et al, 2001;Pu et al, 1998;Rahman et al, 2004;Sramkova et al, 1999), inductively coupled plasma mass spectrometry (Chiba et al, 1992), inductively coupled plasma atomic emission spectrometry (Argekar et al 1995), fluorimetry (Kabasakalis, 1994), stripping voltammetry (Damien, 1994).…”

Direct electrothermal atomic spectrometric determination of Ag in aqua regia extracts of soils, sediments, and sewage sludge with matrix modification

“…Different chemical modifiers were previously more or less effectively applied to attenuate the interferences from chloride matrix for determination of silver (Bermejo-Barrera et al 1996Bhattacharyya 1994;Byrne et al 1993;da Silva et al 1998da Silva et al , 1999Hamalainen et al 1988;Sen Gupta and Bouvier 1994;Slaveykova and Tsalev 1992;Sramkova et al 1999) mostly for sea water samples (Bermejo-Barrera et al 1996da Silva et al 1998;Sen Gupta and Bouvier 1994). The modifiers used were NH 4 H 2 PO 4 (Bermejo- Barrera et al 1996;Hamalainen et al 1988), tartaric acid (Sramkova et al 1999), Pd(CH 3 COO) 2 (Bhattacharyya 1994), Ir, Rh, Ir+Rh (da Silva et al 1998), Ru (da Silva et al 1999, Pd, Pd+Mg, Pd+ ascorbic acid, Pd + HONH 3 Cl, Mg, and HNO 3 (Bermejo- Barrera et al 1996Barrera et al , 1998.…”

“…The modifiers used were NH 4 H 2 PO 4 (Bermejo- Barrera et al 1996;Hamalainen et al 1988), tartaric acid (Sramkova et al 1999), Pd(CH 3 COO) 2 (Bhattacharyya 1994), Ir, Rh, Ir+Rh (da Silva et al 1998), Ru (da Silva et al 1999, Pd, Pd+Mg, Pd+ ascorbic acid, Pd + HONH 3 Cl, Mg, and HNO 3 (Bermejo- Barrera et al 1996Barrera et al , 1998. The most efficient chemical modifiers were platinum group elements, which thermally stabilized the analyte, thus higher pyrolysis temperatures such as 1,000°C and more could be used.…”

Wire-Coated Silver(I) Ion-Selective Electrode Based on 2-Mercaptobenzothiazole (MBT) Ionophore: Application to the Determination of Silver in Real Samples

“…Various methods for the determination of silver at trace quantities have been proposed. They include spectrophotometry, [3][4][5] atomic absorption spectrometry, [6][7][8][9][10] inductively coupled plasma-mass spectrometry, 11 fluorometry, 12 stripping voltammetry, 13 flowinjection analysis, 14 electroanalysis 15,16 and radioisotope dilution. 17 Most of these methods, in spite of their good sensitivities, are very expensive and time consuming in practice; however, potentiometric methods, by using well-tailored ionselective electrodes, have the advantages of selectivity, cheapness and ease of operation.…”