Selective transfer of target heavy metal ions with a simple water-droplet modified approach

Here we propose a new and facile route based on a water-droplet modified approach to explore the voltammetric processes for a series of typical heavy metal ions at the water|1,2-dicholorethane (W|DCE) interface. This convenient method having a selective transfer characteristic indicates that a higher concentration of target ion setting can avoid the masking transfers from other interferential species. The determined Gibbs transfer energies follow an order, Pb2+ < Cd2+ < Mn2+ < Zn2+ < Co2+, Cu2+ < Ni2+, that is consistent with the ionic radius dependence on the Gibbs transfer energies described by the Born solvation model. This powerful methodology thus makes it attractive as a general strategy to probe into the direct transfer of various highly hydrophilic ions.