Chemical gating of a molecular bilayer rectifier at clay-modified electrodes

Journal Article · Wed Apr 14 04:00:00 EDT 1993 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00060a022· OSTI ID:6458994

Rong, Daiting; Mallouk, T E ^[1]

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1. Univ. of Texas, Austin (United States)

Conductive SnO[sub 2] electrodes modified with a 1-2 monolayer thick coating of a cationic silane bind Al[sub 13]O[sub 4](OH)[sub 28][sup 3+]-pillared montmorillonite. The cationic polymer provides binding sites, which are electrochemically accessible to the SnO[sub 2] electrode, for iron(III) tetrakis(4-sulfonatophenyl)porphyrin (FeTPPS[sup 3[minus]]) anions. Electroactive cations such as Ru(NH[sub 3])[sub 6][sup 3+] and Os(bpy)[sub 2]pyCl[sup +] adhere to the clay surface, at sites too remote for direct electron transfer with the electrode, and oxidation/reduction of these ions is mediated by FeTPPS[sup 3[minus]]. The axial ligation of the metalloporphyrin anions changes reversibly with solution pH, and in weakly basic solutions electron transfer between these anions and the electrode is very slow. Cyclic voltammetry and UV-visible spectroscopy show that the FeTPPS[sup 3[minus]] contained within the silane film behaves as a pH-sensitive gate for electron transfer to and from the cations bound to the clay surface. When the formal potential of the clay-bound cation is sufficiently different from that of FeTPPS[sup 3[minus]], proton-gated current rectification can be observed electrochemically. 20 refs., 5 figs.

• DOE Contract Number: FG05-87ER13789
• OSTI ID: 6458994
• Journal Information: Inorganic Chemistry; (United States), Journal Name: Inorganic Chemistry; (United States) Vol. 32:8; ISSN 0020-1669; ISSN INOCAJ
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400* -- Electrochemistry
ABSORPTION SPECTROSCOPY
ALUMINIUM COMPOUNDS
ALUMINIUM HYDROXIDES
ALUMINIUM OXIDES
AMINES
AZINES
BIPYRIDINES
CARBOXYLIC ACIDS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL REACTIONS
CHEMISTRY
CLAYS
COMPLEXES
ELECTROCHEMISTRY
ELECTRODES
ELECTRON TRANSFER
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
HYDRIDES
HYDROGEN COMPOUNDS
HYDROXIDES
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
IONS
IRON COMPLEXES
MATERIALS
MONTMORILLONITE
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC SILICON COMPOUNDS
OSMIUM COMPLEXES
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PH VALUE
PORPHYRINS
PYRIDINES
REDUCTION
RUTHENIUM COMPLEXES
SILANES
SILICON COMPOUNDS
SPECTROSCOPY
TIN COMPOUNDS
TIN OXIDES
TRANSITION ELEMENT COMPLEXES
VOLTAMETRY