Photocatalytically driven dissolution of macroscopic nickel surfaces

Photocatalytically generated H2O2-driven nickel dissolution has been studied as a novel, secondary waste minimal decontamination process for nuclear process steels. Nickel corrosion experiments in dilute H2SO4 show that at deliberately added [H2O2] ≤ 1 mM, nickel dissolution occurs via formation and dissolution of NiOH groups; at [H2O2] ≥ 10 mM (pseudo-)passivation by NiO prevents this. Furthermore, Nickel also dissolves slowly in mild acid, dissolution that is significantly accelerated in the presence of photogenerated peroxide - suggesting that photocatalytically generated H2O2 could be used to selectively increase dissolution of Ni, and potentially steel, surfaces that normally dissolve only slowly in mild acid.