| Autor: |
Fred C. Anson, Grant M Kloster |
| Rok vydání: |
1999 |
| Předmět: |
|
| Zdroj: |
Electrochimica Acta. 44:2271-2279 |
| ISSN: |
0013-4686 |
| DOI: |
10.1016/s0013-4686(98)00344-2 |
| Popis: |
A previously described procedure for coating electrodes with multiple layers of heteropolyanions and charge-balancing dipositive cations [1] was extended to incorporate catalytically active reactants in the coatings. Clear electrocatalytic activity was demonstrated for both anionic ([P 2 Mo 18 O 62 ] 6− ) and cationic ([ cis -Ru(dcbpy) 2 (OH 2 ) 2 ] 2+ (dcbpy=6,6′-dichloro-2,2′-bipyridine)) components of coatings on roughly polished edge plane pyrolytic graphite electrodes. However, the stacking of multilayers on top of the first layer of [P 2 Mo 18 O 62 ] 6− adsorbed on the electrode produced almost no increase in catalytic currents for the reduction of HNO 2 to N 2 O and the activity of [ cis -Ru(dcbpy) 2 (OH 2 ) 2 ] 2+ in coatings toward the catalytic oxidation of benzyl alcohol was short-lived. The behavior observed provided insight into the features that must be controlled to obtain useful coatings consisting of multilayers of electrocatalysts. The kinetics of the reduction of HNO 2 by [H 2 P 2 Mo 18 O 62 ] 6− with both reactants present in solution were also examined. The reaction produces N 2 O and a rate constant for the process of 3.5×10 2 M −1 s −1 was estimated from rotating disk voltammetric measurements. O 2 does not react with the reduced complex, [H 2 Mo 18 O 62 ] 6− , but during its reaction with HNO 2 any O 2 also present undergoes catalytic reduction. The intermediate proposed to be involved in both catalytic reactions is an adduct formed by the reaction of HNO 2 with [H 2 P 2 Mo 18 O 62 ] 6− . |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect