Electrocatalytic dehalogenation of 1,2-dihaloethanes by the C{sub 60}, C{sub 70}, C{sub 76}, C{sub 78}, and C{sub 84} fullerene anions: Structure-reactivity aspects

Journal Article · Thu Apr 15 04:00:00 EDT 1999 · Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical

DOI:https://doi.org/10.1021/jp984780y· OSTI ID:347527

D`Souza, F; Choi, J ^[1]; Kutner, W ^[2]

---

1. Wichita State Univ., KS (United States). Dept. of Chemistry
2. Polish Academy of Sciences, Warsaw (Poland). Inst. of Physical Chemistry

The homogeneous electrocatalytic reduction of 1,2-dihaloethanes by anions of larger fullerenes, C{sub 76}, C{sub 78}, and C{sub 84}, is presented, and structure-reactivity correlations are derived by including the data reported earlier for the C{sub 60} and C{sub 70} electrocatalytic process. Cyclic voltammetry measurements indicate that dianions of C{sub 76} and C{sub 78}, as well as trianions of C{sub 76}, C{sub 78}, and C{sub 84}, electrochemically generated in 0.1 M (TBA)PF{sub 6}, in benzonitrile, catalyze dehalogenation of 1,2-dihaloethanes. Values of the second-order rate constant, {kappa}, for the electrocatalytic dehalogenation of 1,2-dihaloethanes by the fullerene anions were determined by using the rotating-disk electrode voltammetry under pseudo-first-order conditions with respect to the 1,2-dihaloethanes. For each fullerene anion, {kappa} increases in the order: Cl < Br < 1 for the investigated 1,2-dihaloethanes. Also, log {kappa} linearly increases in the order: C{sub 84} < C{sub 78} < C{sub 76} < C{sub 70} < C{sub 60}, as a function of respective redox potentials of the fullerene, for each 1,2-dihaloethane. Unlike the C{sub 60}{sup n{minus}} electrocatalysis, reported by the authors earlier to be accompanied by chemical reaction between C{sub 60}{sup n{minus}} and certain {alpha},{omega}-diiodoalkanes yielding alkyl adducts of C{sub 60}, no reaction between the anions of larger fullerenes and 1,2-dihaloethanes was observed within the voltammetric time scale. Because of the high stability with respect to adduct formation and more positive potentials of the electrocatalyses, the larger fullerenes may be more useful than C{sub 60} as catalysts, even though the corresponding catalytic rate constants are smaller.

• OSTI ID: 347527
• Journal Information: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical, Journal Name: Journal of Physical Chemistry B: Materials, Surfaces, Interfaces, amp Biophysical Journal Issue: 15 Vol. 103; ISSN 1089-5647; ISSN JPCBFK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
40 CHEMISTRY
CHEMICAL REACTION KINETICS
CORRELATIONS
ELECTROCATALYSTS
ETHANE
FULLERENES
HALOGEN COMPOUNDS
MICROSTRUCTURE
REDUCTION
VOLTAMETRY