Nickel hydroxide with structural defects for sensitive detection of Pb(II) and Cd(II) ions in aqueous media

The strong electrostatic interactions between the nickel ions and the hydroxy atoms in the vicinity of stacking faults could contribute to the improvement of electrochemical activity. In this work, β-Ni(OH)2 of ∼5 nm crystallite size and an abundance of stacking faults have been prepared via a rather simple chemical precipitation method. The sensor, based on β-Ni(OH)2 modified glassy carbon electrode is employed to determine the trace level of Pb(II) and Cd(II). A high detection sensitivity is achieved for Pb(II) of 22. 29 AM−1 and Cd(II) of 14.05 AM−1, with a limit of detection of ∼0.6 nM and ∼0.9 nM, respectively. The fabricated sensor has been successfully used to analyze Pb(II) and Cd(II) in river water. The results are comparable to the ones obtained using ICP-MS, indicating the accuracy of the measurements from the modified electrode.