Catalytic effects in the electrochemical reactions involving nickel and cysteine. Voltammetric studies

The electrode reactions in the nickel-cysteine system at pH-values around 7 were studied by cyclic voltammetry on the hanging mercury drop electrode. The following processes are induced by cysteine:1) the catalytic reduction of the nickel ion; 2) the anodic dissolution of the nickel amalgam by a catalytic mechanism; 3) the catalytic evolution of hydrogen. Some analogies with the behaviour of the nickel center in hydrogenase are suggested.