El Ghachtouli S.,University Paris - Sud |
El Ghachtouli S.,Laboratoire Interface Materiaux Environnement |
Lassalle-Kaiser B.,CEA Saclay Nuclear Research Center |
Lassalle-Kaiser B.,Synchrotron Soleil |
And 3 more authors.
European Journal of Inorganic Chemistry
We report the synthesis of a pentadentate N4O ligand with an imidazole group in the ortho position of the phenol group. The syntheses and crystallographic structures are reported for zinc(II) complexes by using the previously reported tert-butyl-substituted ligand and the imidazole-substituted ligand in two different protonation states. We describe the influence of the ortho substituent (tert-butyl, imidazole, and imidazolium) on the electrochemical behavior of the zinc(II) complexes. The substitution of the tert-butyl group in the ortho position by an imidazole group shifts the oxidation potential of the phenolate by more than 300 mV. The o-tert-butyl-substituted ligand allows the formation of a stable radical phenoxylzinc(II) complex upon electrochemical oxidation, but it is unstable in the case of the imidazole-substituted complex. The imidazole-substituted ligand can be reversibly protonated without altering the electrochemical properties of the phenolate group. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source
Hliwa L.,Laboratoire Interface Materiaux Environnement |
Azzi M.,Laboratoire Interface Materiaux Environnement |
Bennani A.,Laboratoire Interface Materiaux Environnement |
Saib N.,Laboratoire Interface Materiaux Environnement |
And 2 more authors.
Journal of New Materials for Electrochemical Systems
The electrochemical study shows that phosphate ions oxidation on BDD (Boron Doped Diamond) occurs before oxygen evolution in aqueous mild. The reaction rate is enhanced in a basic solution. With voltametric studies it is shown that oxidation current is linearly dependent on phosphate ions concentration and potential scan rate. The electro-chemical mechanism is very complex and involves several steps with adsorbed species and radicals. The electrolysis at fixed potential leads to peroxodiphosphate species formation in solution. The complexity of electrochemical mechanism is confirmed by EIS study. EIS measurements demonstrate also that BDD electrodeelectrolyte behavior is compatible to p-type semiconductor with 1.49 V as plate band potential. © J. New Mat. Electrochem. Systems. Source