Comparison of the charge-transport rate in two redox levels of polymers derived from N,N'-dibenzyl-4,4'-bipyridinium and N,N'-dialkyl-4,4'-bipyridinium

Journal Article · Wed Nov 14 04:00:00 EST 1984 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00335a012· OSTI ID:5973561

Lewis, T J; White, H S; Wrighton, M S

Charge transport in electrode-confined polymers derived from N,N'-bis(p-(trimethoxysilyl)benzyl)-4,4'-bipyridinium dichloride, ((BPQ/sup 2+/+/0/)/sub n/)/sub surf/, and N,N'-bis((trimethoxysilyl)propyl)-4,4'-bipyridinium dibromide, ((PQ/sup 2+/+/0)/sub n/)/sub surf/, has been studied. Specifically, a comparison of charge transport in the 2+/+ and +/0 redox systems of both polymers has been made. Interestingly, +/0 has an effective diffusion coefficient for charge transport, D/sub CT/, that is significantly greater than that for the 2+/+ redox level in H/sub 2/O/CH/sub 3/CN (9/1 by volume) 1.0 M LiCl. Platinum disk electrodes have been studied that have polymer thicknesses up to approx. 2.5 ..mu..m in the 2+ state corresponding to a coverage of approx. 7.5 x 10/sup -7/ mol of monomer units per cm/sup 2/. Up to a 30-40% decline in thickness is observed upon reducing the polymer from the 2+ to the 0 state. Values of the products D/sub CT/C/sup 2/, where C is the concentration of monomer units in the + or 0 state of the polymer, have been determined by measuring the current for reduction of Ru(NH/sub 3/)/sub 6//sup 3 +/ at polymer-coated rotating disks as a function of polymer coverage. The data support the conclusion that >20 mA/cm/sup 2/ can be maintained when the polymer thickness in the 2+ state is 1.0 ..mu..m, corresponding to a coverage of approx. 2 x 10/sup -7/ mol/cm/sup 2/ of monomers per cm/sup 2/. 10 references, 7 figures, 1 table.

• Research Organization: Massachusetts Inst. of Tech., Cambridge
• OSTI ID: 5973561
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 106:23; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400* -- Electrochemistry
ACETONITRILE
ALKALI METAL COMPOUNDS
ALKANES
AROMATICS
AZINES
BIPYRIDINES
BROMIDES
BROMINE COMPOUNDS
CHARGE TRANSPORT
CHEMICAL REACTIONS
CHLORIDES
CHLORINE COMPOUNDS
COMPARATIVE EVALUATIONS
CURRENT DENSITY
DATA
DATA ANALYSIS
DIFFUSION
DISPERSIONS
ELECTRODES
ELEMENTS
EXPERIMENTAL DATA
FILMS
HALIDES
HALOGEN COMPOUNDS
HETEROCYCLIC COMPOUNDS
HYDROCARBONS
HYDROGEN COMPOUNDS
INFORMATION
LITHIUM CHLORIDES
LITHIUM COMPOUNDS
LITHIUM HALIDES
METALS
MIXED SOLVENTS
MIXTURES
NITRILES
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC POLYMERS
OXYGEN COMPOUNDS
PLATINUM
PLATINUM METALS
POLYMERS
PYRIDINES
REDOX REACTIONS
SILICON COMPOUNDS
SOLVENTS
THIN FILMS
TRANSITION ELEMENTS
VOLTAMETRY
WATER