Redox chemistry of the Keggin heteropolyoxotungstate anion in ionic liquids.

Journal Article · Tue Jun 01 04:00:00 EDT 2004 · J. Electroanal. Chem.

DOI:https://doi.org/10.1016/j.jelechem.2003.11.062· OSTI ID:961417

Chiang, M -H; Dzielawa, J A; Dietz, M L; Antonio, M R

The solid salts of the 1-ethyl-3-methylimidazolium and the 1-n-pentyl-3-methylimidazolium cations, abbreviated [C{sub 2}mim]{sup +} and [C{sub 5}mim]{sup +}, respectively, of the Keggin heteropolyanion, {alpha}-[PW{sub 12}O{sub 40}]{sup 3-}, were prepared. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements of both [C{sub n}mim]{sub 3}[{alpha}-PW{sub 12}O{sub 40}] salts (for n=2 and 5) were performed in acetonitrile containing either tetra-n-butylammonium hexafluorophosphate, abbreviated TBAPF{sub 6}, or the corresponding [C{sub n}mim]BF{sub 4} ionic liquids (ILs) as electrolytes. The results are compared with the corresponding data obtained in the neat [C{sub n}mim]BF{sub 4} ILs without addition of other electrolytes. The effects of countercation and supporting electrolyte on the voltammetry of the Keggin ion {alpha}-[PW{sub 12}O{sub 40}]{sup 3-} are interpreted as resulting from an amalgamation of isomerization, ion-association, and redox processes. The combination of the unique solvent/electrolyte properties of ILs with the well-known electrochemistry of molecular polyoxometalates (POMs) like the Keggin aanion leads to redox behavior that may have impact on the research and technology of catalytic and energy-storage phenomena.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 961417
• Report Number(s): ANL/CHM/JA-47536
• Journal Information: J. Electroanal. Chem., Journal Name: J. Electroanal. Chem. Journal Issue: 1 ; Jun. 1, 2004 Vol. 567; ISSN JEACAX; ISSN 0368-1874
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ACETONITRILE
ANIONS
CATIONS
ELECTROCHEMISTRY
ELECTROLYTES
ENERGY STORAGE
IONS
ISOMERIZATION
LIQUIDS
SALTS
SOLIDS