TY - JOUR
T1 - Molybdenum-sulfur dimers as electrocatalysts for the production of hydrogen at low overpotentials
AU - Appel, Aaron M.
AU - DuBois, Daniel L.
AU - Rakowski DuBois, M.
PY - 2005/9/14
Y1 - 2005/9/14
N2 - (CpMoμ-S)2S2CH2, 2, and related derivatives serve as electrocatalysts for the reduction of protons with current efficiencies near 100%. The kinetics of the electrochemical reduction process has been studied, and the effects of varying the proton source, the solvent, the cyclopentadienyl substituents, and the sulfur substituents on the catalyst have been examined. The reduction of excess p-cyanoanilinium tetrafluoroborate under a hydrogen atmosphere in 0.3 M Et4NBF4/acetonitrile buffered at pH 7.6 is catalyzed by 2 at -0.64 V versus ferrocene, with an overpotential of 120 mV. Protonation of the sulfido ligand in 2 is an initial step in the catalytic process, and the rate-determining step at high acid concentrations appears to be the elimination of dihydrogen. The elimination may occur either from adjacent hydrosulfido sites or from a hydrosulfido-molybdenum hydride intermediate.
AB - (CpMoμ-S)2S2CH2, 2, and related derivatives serve as electrocatalysts for the reduction of protons with current efficiencies near 100%. The kinetics of the electrochemical reduction process has been studied, and the effects of varying the proton source, the solvent, the cyclopentadienyl substituents, and the sulfur substituents on the catalyst have been examined. The reduction of excess p-cyanoanilinium tetrafluoroborate under a hydrogen atmosphere in 0.3 M Et4NBF4/acetonitrile buffered at pH 7.6 is catalyzed by 2 at -0.64 V versus ferrocene, with an overpotential of 120 mV. Protonation of the sulfido ligand in 2 is an initial step in the catalytic process, and the rate-determining step at high acid concentrations appears to be the elimination of dihydrogen. The elimination may occur either from adjacent hydrosulfido sites or from a hydrosulfido-molybdenum hydride intermediate.
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U2 - 10.1021/ja054034o
DO - 10.1021/ja054034o
M3 - Article
C2 - 16144422
AN - SCOPUS:24744468030
VL - 127
SP - 12717
EP - 12726
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 36
ER -