Electrodes with extremely high hydrogen overvoltages as substrate electrodes for stripping analysis based on...

Hydrogen evolution bothers stripping analysis significantly. Dioctyl phthalate-based carbon paste electrode exhibits extremely wide cathodic potential window. It is explored as a powerful substrate electrode to solve the problem of hydrogen evolution and further improve reproducibility for stripping analysis using bismuth-coated electrodes for the first time. It was successfully applied to the simultaneous determination of Zn(2+), Cd(2+), and Pb(2+). Linear responses are obtained for Zn(2+) in the range of 10-100μgL(-1) and for Pb(2+) and Cd(2+) in the range of 5-100μgL(-1). The detection limits for Zn(2+), Cd(2+), and Pb(2+) are 0.1μgL(-1), 0.22μgL(-1) and 0.44μgL(-1), respectively. The method has been successfully applied to the determination of Zn(2+), Cd(2+), and Pb(2+) in waste water samples. The detection strategy based on the combination of dioctyl phthalate-based carbon paste electrode and bismuth-coated electrodes holds great promise for stripping analysis.