As a suitable alternative approach to chemical hydride generation (HG) techniques, electrochemical HG (ECHG) has been used as a sample introduction method for spectrometric determination of Hg and hydride forming elements (HFEs), such as, As, Bi, Cd, Ge, Pb, Sb, Se, Sn, Te, Tl and Zn because of its advantages. It would be challenging and interesting to expand the ECHG to other HFEs. In this work, electrolytic HG system coupled to an electrically-heated quartz tube atomic absorption spectrometry (QTA-AAS) has been developed and optimized for determination of trace amounts of Ag and Cu in aqueous solutions. A laboratorymade semi-batch cell with Pb-Sn cathode was used as hydride generator based on the electrolytic reduction of Ag and Cu ions to their unstable volatile molecular species. Scanning electron microscopic (SEM) analysis has been used to study the mechanism of hydride generation from the cathode surface. The method is based on the reaction between electrochemically generated hydrogen atoms on the cathode surface of electrolytic cell and the deposited elements. The influence of the experimental parameters on the analytical response was studied. Under the optimized conditions, the calibration curve was linear in the range of 3-200 ng mL-1 of Ag. A concentration detection limit (3b, n=6) of 1.2 ng mL-1 Ag and a relative standard deviation of 3.2% (RSD, n=8) for 100 ng mL-1 Ag were obtained. the detection limit (3b, n=3) was found to be 0.3 mg L-1 Cu and the RSD for six replicate analyses of 10 mg L-1 Cu was 4.3%. The calibration curve was linear in the range of 5-100 mg L-1 of Cu. The potential interferences from various ions were also evaluated. Although the achieved detection limit is poor for Cu; however the proposed procedure is rapid, relatively simple, low cost and sensitive especially for Ag.

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