An electrochemical hydride generation (ECHG) techniquewas developed to improve the determination of thallium by atomic ‎spectrometry. The technique is based on the catholyte variation system for production of thallium hydride. Using Pb–Sn alloy as cathode, a ‎transient peak shaped signal was achieved and its height, the maximum absorbance value, was taken as an analytical parameter. ‎Parameters that might affect the hydride generation efficiency were investigated and the analytical performance of the method under the ‎optimized experimental conditions was assessed. The linear range was 1–250 ngmL−1 for thallium and the relative standard deviation of the ‎method was 4.2% (RSD, n = 7). The LOD for thallium was found to be 0.8 ngmL−1, showing a significantimprovement relative to ‎conventional chemical hydride generation techniques. The proposed method was applied to the determination of thallium in unalloyed zinc ‎standard reference material. This method offers high sensitivity, simplicity, rapidness, freeness from reagent and low acid consumption.‎

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