TY - JOUR
T1 - Mechanism of the electroreduction of Ni (II) ions on mercury electrodes catalyzed by pyridine and its derivatives
T2 - Nicotinamide, N,N-diethylnicotinamide and nicotine: Concept of parallel heterogeneous catalytic reactions
AU - Tur'yn, Yakov I.
AU - Mata, Fernando
AU - Moyano, Jorge
AU - Gorenbein, Pavel
AU - Kohen, Ron
PY - 2006/11
Y1 - 2006/11
N2 - The theory of the polarographic catalytic currents (mechanism CE) has been developed for the system: Ni2+-L-Xp- where L: pyridine (Py), nicotinamide (NA), N,N-diethylnicotinamide (DEN), nicotine (NC) and X p-: NO- 3, AcO-, HPO2- 4 . The theory is based on the kinetic parallel heterogeneous catalytic reactions: equation presented with the use of Langmuir's adsorbed isotherm. The kinetic equations obtained for average and instantaneous currents allowed to determine the Langmuir's parameters (NA<DEN<NC), kinetic parameters and the contribution of reactions 1a and b to the summary catalytic currents. The k″h value rises with the increase of the NiX 2-p stability constant. The correlation k″ h≤k″h was explained by the additional effect of the field electrode through Xp-. These effects base the reaction 1b instead of accepted early alternative reaction of the ligand exchange. In spite of the fact that k″h≤k″h, the contribution of the reaction 1a in the summary catalytic current attained more than 60% (Py, DEN) due to the influence of the ψ0 potential.
AB - The theory of the polarographic catalytic currents (mechanism CE) has been developed for the system: Ni2+-L-Xp- where L: pyridine (Py), nicotinamide (NA), N,N-diethylnicotinamide (DEN), nicotine (NC) and X p-: NO- 3, AcO-, HPO2- 4 . The theory is based on the kinetic parallel heterogeneous catalytic reactions: equation presented with the use of Langmuir's adsorbed isotherm. The kinetic equations obtained for average and instantaneous currents allowed to determine the Langmuir's parameters (NA<DEN<NC), kinetic parameters and the contribution of reactions 1a and b to the summary catalytic currents. The k″h value rises with the increase of the NiX 2-p stability constant. The correlation k″ h≤k″h was explained by the additional effect of the field electrode through Xp-. These effects base the reaction 1b instead of accepted early alternative reaction of the ligand exchange. In spite of the fact that k″h≤k″h, the contribution of the reaction 1a in the summary catalytic current attained more than 60% (Py, DEN) due to the influence of the ψ0 potential.
KW - Catalysis by pyridine and its derivatives
KW - Kinetic and adsorbed parameters
KW - Nickel (II) catalytic systems
KW - Parallel heterogeneous catalytic reactions
KW - Polarographic catalytic currents
UR - http://www.scopus.com/inward/record.url?scp=33749616074&partnerID=8YFLogxK
U2 - 10.1007/s10008-005-0017-7
DO - 10.1007/s10008-005-0017-7
M3 - Article
AN - SCOPUS:33749616074
SN - 1432-8488
VL - 11
SP - 10
EP - 20
JO - Journal of Solid State Electrochemistry
JF - Journal of Solid State Electrochemistry
IS - 1
ER -