The electrochemistry of C[sub 60] and scanning electrochemical microscopy studies of electrohydrodimerization reactions

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1993

OSTI ID:6970488

Zhou, Feimeng

The electrochemistry of C[sub 60] in two different solvent systems is described in the first part of this thesis. Reduction of a C[sub 60] slurry in liquid ammonia/KI and liquid ammonia/LiI at [minus]70[degrees]C by one equivalent of electrochemically generated solvated electrons produced a C[sub 60][minus] solution. In liquid NH[sub 3]/KI solution, cyclic voltammetry (CV) shows five stepwise reductions to C[sub 60][sup 6[minus]], and one oxidation to C[sub 6]. Four stepwise reductions to C[sub 60][sup 5[minus]] were observed when LiI was used as the supporting electrolyte. Coulometric titrations were performed to identify the formation of the C[sub 60][sup 6[minus]] ion in NH[sub 3]/KI and NH[sub 3]/(TBA)CF[sub 3]SO[sub 3] (TBA = tetra-n-butylammonium) solutions. Thin films of C[sub 60] formed by solution casting were studied in acetonitrile by CV, scanning electrochemical microscopy (SECM) and quartz crystal microbalance (QCM). The CV behavior for the first reduction indicates a large structural reorganization of the film with intercalation of the supporting electrolyte cation. SECM studies of the C[sub 60] films show that neither the C[sub 60] film nor the completely reduced, C[sub 60][sup [minus]], form is a good electronic conductor, while a partially reduced film displays enhanced conductivity. SECM and QCM were also used to estimate the extent of dissolution of the C[sub 60] film upon reduction to the C[sub 6][minus] and C[sub 60][sup 2[minus]] forms. SECM studies of electrohydrodimerization reactions of dimethylfumarate, fumaronitrile and acrylonitrile in N,N-dimethylformamide are described in this thesis. Both feedback and generation/collection modes are assessed. The feasibility of measuring second-order homogeneous chemical reactions using SECM is shown by the study of dimethylfumarate and fumaronitrile. The capability of SECM to study very fast chemical reactions is demonstrated by the detection of acrylonitrile anion radical.

• Research Organization: Texas Univ., Austin, TX (United States)
• OSTI ID: 6970488
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201 -- Chemical & Physicochemical Properties
400400* -- Electrochemistry
ALKALI METAL COMPOUNDS
CARBON
CARBOXYLIC ACIDS
CHEMICAL REACTIONS
CHEMISTRY
DICARBOXYLIC ACIDS
DIMERIZATION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTROCHEMISTRY
ELEMENTS
FULLERENES
FUMARIC ACID
HALIDES
HALOGEN COMPOUNDS
INORGANIC PHOSPHORS
IODIDES
IODINE COMPOUNDS
LITHIUM COMPOUNDS
LITHIUM HALIDES
LITHIUM IODIDES
MICROSCOPY
NITRILES
NONMETALS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOSPHORS
PHYSICAL PROPERTIES
POLYMERIZATION
POTASSIUM COMPOUNDS
POTASSIUM IODIDES
REDUCTION