New voltammetric sensor based on the renewable bismuth bulk annular band electrode and its application for the determination of palladium(II)

A study of a new type of voltammetric sensor based on the renewable bismuth bulk annular band working electrode (RBiABE) for palladium(II) detection via differential pulse adsorptive stripping voltammetry (DP AdSV) after complexation with dimethylglyoxime (DMG) in an acetate buffer (pH 4.1) and without deaeration is reported. The experimental variables (composition of the supporting electrolyte, pH, potential and time of pre-concentration and DP parameters) as well as possible interferences were investigated and optimized. The peak current was proportional to the concentration of Pd(II) over the range from 9.4 × 10−8 to 9.4 × 10−6 mol L−1 (R = 0.9993) and from 9.4 × 10−9 to 9.4 × 10−8 mol L−1 (R = 0.9995) for accumulation times of 10 s and 40 s, respectively. For 40 s of accumulation time, the limit of detection was 8.9 × 10−10 mol L−1 (0.12 μg L−1) (at S/N = 3), with a sensitivity of 0.84 nA/nM. The relative standard deviation for 9.4 × 10−8 mol L−1 Pd(II) was 5.1% (n=5). Finally, the proposed method was successfully applied and validated by studying the recovery of Pd(II) from spiked tap and river water samples.