▎ 摘　　要

A very sensitive electrochemical sensor based on a reduced graphene oxide film impregnated with antimony nanoparticles was prepared and applied to the electroanalysis of platinum group metal ions of Pd(II), Pt(II) and Rh(III). The electrochemical behavior of platinum group metals at the modified electrode was studied by adsorptive differential pulse cathodic stripping voltammetry in the presence of dimethylglyoxime as chelating agent. Several operational parameters were optimised to enhance the electroanalytical performance of the modified glassy carbon electrode sensor. The results showed sharp stripping peaks and a relatively constant peak potential with a good linear behaviour in the examined concentration range from 40 to 400 pg L-1 for all metal ions investigated. The detection limit was found to be 0.45, 0.49 and 0.49 pg L-1 (S/N=3) for Pd(II), Pt(II) and Rh(III), respectively. The developed electrochemical sensor also exhibited good precision with a relative standard deviation of 4.2%, 2.55% and 2.67% for 5 successive measurements for Pd(II), Pt(II) and Rh(III), respectively. The proposed nanostructure showed good sensitivity and stability, which has promising potential applications in electrochemical sensors.