| Two objectives were set for this work: first, is to determine the ICP discharge temperature as a function of the radio frequency forward power output. Second, is to improve on the analytical performance of the hydride preconcentration on palladium inside a graphite furnace with ICP-MS detection.;The plasma discharge thermodynamic temperature has been estimated using both N;Preconcentration of multi element volatile hydrides in a graphite furnace and the subsequent determination by ICP-MS is a relatively new method for elemental analysis. The hydrides of arsenic, bismuth, and tellurium were trapped in the presence of metallic palladium inside a graphite tube of an electrothermal vaporization unit, and subsequently determined by ICP-MS in a single run. The linearity obtained using this method was limited to a sub-ng/ml concentrations. Effectiveness of the method was determined by analyzing a standard reference material.;One approach to achieve better analyte trapping efficiency is to increase the available palladium surface area. Strips of tungsten, tantalum, molybdenum, and rhenium were coated (electroplated, and sputtered) with palladium and used as a platform inside the graphite furnace. The Pd surface roughness and coverage were determined by scanning electron microscopy and x-ray fluorescence techniques.;The Pd-coated tungsten platform (0.1 mm thick) showed the best performance in trapping and revolatilizing the analyte. This platform retained the palladium over an extended number of firings, more than 80 in this study. Utilization of this platform improved the linearity of the method to better than two orders of magnitude. The concentration limit of detection obtained in this work was 11 pg/ml. Rhenium, molybdenum, and tantalum were found not a suitable substrate in this study. |
