Nickel-based nanoporous electrodes for water treatment

In this work nickel (Ni) nanoporous electrodes have been prepared by selective electrochemical dissolution of copper (Cu) from Ni-Cu deposits. The anodic dissolution of Cu was carried out in aqueous solutions containing boric acid (0.5M) using both constant voltage and pulsed voltage waveforms. Scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and Auger electron Spectroscopy (AES) showed that porous nickel foams with average size of 100-300 nm have been obtained under the operative conditions adopted. The electrodes have been characterized by cyclic voltammetry (CV) and linear sweep voltammetry (LSV) in alkaline solutions in order to investigate the electrocatalytic activity of porous nickel electrodes towards the oxygen evolution reaction (OER) and the removal of phenol, used as model of pollutant compounds. The results demonstrated that nickel porous electrodes show electrocatalytical activity towards OER and are able to decrease the concentration of phenol in alkaline solutions.