Palladium as a Matrix Modifier in Graphite-Furnace Atomic Absorption Spectrometry of Group IIIB - VIB Elements

Abstract

The performances of palladium as a matrix modifier for group IIIB -VIB elements in graphite-furnace atomic absorption spectrometry were compared to those of other modifiers hitherto reported.The application of palladium and mixed modifiers containing palladium to biological, mineral sediment or natural water samples is summarized.The addition of palladium generally makes a higher thermal pretreatment temperature possible without any sensitivity loss, thus reducing the interferences of coexisting materials.Mass spectrometry connected to graphite-furnace atomic absorption spectrometry enabled real-time observations of the vaporized species in the furnace and revealed the vaporization and atomization process of arsenic and selenium in the presence of palladium.Both elements form compounds PdnMm01(M=As or Se), which are then decomposed to PdM and finally to atomic vapor of M.

Release of selenium and tin from the graphite support in the presence of tungsten and palladium modifiers

“…It is possible that the analyte is vaporized from the surface of the droplets [13]. The existence of various compounds between Pd and Se or Sn is shown using the different instrumental methods -SEM, ~tEDXRD [14][15][16]. Indirectly the possibility to form [Pd, Se, O] species during pyrolysis and vaporization of Se from that mixture also was shown by scanning electron microscopy [17].…”

Determination of Heavy Metals at Sub-ppb Levels in Water by Graphite Furnace Atomic Absorption Spectrometry Using a Direct Introduction Technique after Preconcentration with an Iminodiacetate Extraction Disk

“…When the analytes (Co, Ni, Cu, Cd, Sn, Pb, and Bi) on a small disk (2 mm diameter) from the IED were atomized under the above-mentioned conditions, the absorbancetime profiles of only Pb and Bi showed double peaks consisting of a large first peak and a small second peak, as shown in Figure 2(a). In contrast, when a palladium nitrate solution was added to the small disk as a chemical modifier for the elements of the 13 -16 groups [31] before it was introduced into the furnace, the absorbance-time profiles of Pb and Bi showed a single broad peak, as shown in Figure 2(b). The results suggest that the first peak may be due to vaporization of the analyte element, and the second peak may be attributable to condensation and revaporization of the analyte element.…”

Atomic Absorption Spectrometric Determination of Cadmium and Lead in Human and Artificial Teeth by Direct Atomization Technique

“…To prevent the evaporation of the analytes of the 12-15 groups of elements in the periodic table during the pyrolysis step, Pd was employed as matrix modifier (27). The sensitizing effectiveness of Pd was examined.…”