Chapter 4 - Jacobs University

Chapter 8
Collaborative Work
8.1.2 Electrochemistry of [P 8 W 48 O 184 Fe 16 (OH) 28 (H 2 O) 4 ] 20- (3)
The electrochemical study of 3, which is stable from pH 1 through 7, offers an interesting
example of a highly iron rich cluster. The reduction wave associated with the Fe 3+ centres could
not be split in distinct steps independent of the potential scan rate from 2 to 1000 mVs -1 ; this is in
full agreement with the structure showing that all 16 iron centres are equivalent. Polyanion 1
proved to be efficient for the electrocatalytic reduction of NO x including nitrate.
8.1.3 Electrochemistry of [H 2 Pt IV V 9 O 28 ] 5- (5)
A controlled potential electrolysis performed with the glassy carbon potential set at +0.03
Vshows a consumption of 8 electrons per molecule for both compounds. This couple is attributed
to the reduction of V V centers. Upon potential reversal, oxidation of the resulting dihydrogen is
observed. This hydrogen evolution reaction occurs with a very small over potential. The
deposited Pt film also exhibits high performance in the electro-oxidation of CH 3 OH. Polyanion 3
constitutes a good candidate for elaborating very active carbon-supported Pt nanoparticles,
because it has a perfectly defined molecular stoichiometry, and without chloride present it is not
prone to easy hydrolysis.
8.2 Magnetism
The magnetic studies on polyanion 3 were performed by the group of Prof N. Dalal from the
Department of Chemistry and Biochemistry, Florida State University and National High
Magnetic Field Laboratory and Center for Interdisciplinary Magnetic Resonance, Tallahassee,
Florida 32306-4390. For more detailed info please check Chem. Eur. J. 2008, 14, 1186 in
Appendix.
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