Journal of the American Chemical Society
place at potentials as low as 0.4 V showing that, oxidative
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carbonylation of MeOH does not require metal ions (oxi-
dized metal) as catalyst and that the reaction can take
place directly on the metal, which represents ideal condi-
tions for industrial applications as the catalyst stability is
improved. These results represent an important step fur-
ther in the development of an electrochemical process
understanding for the synthesis of DMC and can help on
the development of more efficient and selective processes
for electrocarbonylation reactions.
ASSOCIATED CONTENT
Supporting Information. Transmission spectra for species
in solution are shown as supporting information. This mate-
rial is available free of charge via the Internet at
AUTHOR INFORMATION
Corresponding Author
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* Marc T. M. Koper
MATERIALS AND METHODS
Present Addresses
The
experiments
were
performed
using
a
†Marta C. Figueiredo
spectroelectrochemical cell with
a
three electrode
configuration as decribed elsewhere 19-20. The working
electrodes (Au, Pd, Pt and Ag) were discs mechanically
polished with alumina suspension, rinsed with MilliQ
water (18.4 MΩ) and sonicated for 5 min before each ex-
periment. A Pt coil was used as counter electrode and an
Ag/AgCl electrode as reference. The electrode potential
was controlled with a Potentiostat 466 System (Model
ER466) from E-DAQ. All the experiments were performed
at room temperature.
University of Copenhagen, Department of Chemistry
Nano-Science Center
Universitetsparken, 5
2100 Copenhagen
DENMARK
The electrolyte solution was prepared with 0.1 M LiClO4
(Fluka, <99%) in Methanol (MeOH, 98% anhydrous from
Sigma Aldrich). Prior to the experiments the solutions
were purged with Ar (6.0 from Linde) to remove all the
oxygen, and blank cyclic voltamograms were obtained.
For the experiments with CO, the solutions was fluxed
with CO (6.0 Linde) during 20 min after oxygen removal.
During the electrochemical/ spectroelectrochemical
measurements, the gas flow was kept in the cell atmos-
phere. For the isotopically labelled experiments, CO with
13C > 99% from Cambridge Isotope laboratories was used.
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ACKNOWLEDGMENT
S. I., Synthesis of dimethyl carbonate by vapor phase oxidative
carbonylation of methanol over Cu-based catalysts. Journal of
Molecular Catalysis A: Chemical 2001, 170 (1–2), 225-234.
The authors acknowledge Covestro Deutschland AG for
the financial support of this project.
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