In this work, the influence of various protic and aprotic organic solvents (methanol (MeOH), ethanol (EtOH), isopropanol (PrOH), acetonitrile (AN), and dimethylsulfoxide (DMSO) on the electrochemical hydride generation (ECHG) of antimony species was evaluated. Stibine (SbH3) has been produced from Sb(III) and Sb(V) by an ECHG batch cell [1,2]. The hydrides, react with silver diethyldithiocarbamate (SDDC) in a basic organic medium and a red colored complex is formed. Detection is performed using a UV-Vis spectrophotometer in the wavelength of 510 nm. The results of the experiments showed a better performance for ECHG in the presence of 4 organic solvents i.e. MeOH, EtOH, PrOH, and AN. Among them, the most effective solvent was AN. DMSO caused a reduction in the efficiency of ECHG systems. For antimony, the analytical performance of the method was evaluated in the optimized conditions (optimized oprating ECHG condition and also optimized solvent and % V/V organic solvent /water) which shows an improved performance of the electrochemical hydride generation systems in the terms of sensitivity and interference tolerance. The proposed method was characterized by a linear calibration range of 10 μg to 60 μg for Sb(III) with a detection limit of 2.29 μg. The relative standard deviation was 5.2% (n = 5) for Sb(III). Also, a linear calibration range of 5 μg to 60 μg and a detection limit of 2.21 was obtained for Sb(V). The relative standard deviation Sb(V) was 7.1% (n = 5).

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