Open AccessIn Situ Study of the Magnetoelectrolysis Phenomenon during Copper Electrodeposition Using Time Domain NMR Relaxometry
Author(s) -
Bruna Ferreira Gomes,
Luiza M. S. Nunes,
Carlos Manuel Silva Lobo,
Luís Fernando Cabeça,
Luiz Alberto Colnago
Publication year - 2014
Publication title -
analytical chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.117
H-Index - 332
eISSN - 1520-6882
pISSN - 0003-2700
DOI - 10.1021/ac502361q
Subject(s) - chemistry , relaxometry , diamagnetism , electron paramagnetic resonance , paramagnetism , nuclear magnetic resonance , analytical chemistry (journal) , electrochemistry , nuclear magnetic resonance spectroscopy , magnetic field , electrode , magnetic resonance imaging , spin echo , condensed matter physics , organic chemistry , medicine , physics , quantum mechanics , radiology
Although the effect of magnetic field (B) on electrochemical reactions (magnetoelectrolysis phenomenon) has been long known, it has not been considered in electrochemical reactions analyzed in situ by magnetic resonance methods, such as nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and magnetic resonance imaging (MRI), which are intrinsically performed in the presence of B. In this report, the effect of B on the copper electrodeposition reaction, measured by a low-field (0.23 T) NMR spectrometer, was demonstrated. As expected, an enhancement in the reaction rate in comparison to the ex situ electrodeposition reaction was observed. Such enhancement was not dependent on electrodes/magnetic field orientations. Parallel and perpendicular orientations showed similar electrodeposition rates, which is explained by the cyclotron flows generated by distortions in electric and magnetic field lines near the electrode and the electrode edge. Therefore, NMR spectroscopy is not a passive analytical method, as assumed in preceding in situ spectroelectrochemical studies. Although the magnetoelectrolysis phenomenon demonstrated in this report used a paramagnetic ion, it can also be observed for diamagnetic species, since the magnetoelectrolysis phenomenon is independent of the nature of the species. Consequently, similar convection effects may occur in other electrochemical nuclear magnetic resonance (EC-NMR) experiments, such as the electrochemical reaction of organic molecules, as well as in electrocatalysis/fuel cells, lithium-ion batteries, and experiments that use electrochemical electron paramagnetic resonance (EC-EPR) and electrochemical magnetic resonance imaging (EC-MRI).