학술논문

Electrodeposited Defect Chemistry Superlattices
Document Type
research-article
Source
Science, 1994 Jun 01. 264(5165), 1573-1576.
Subject
Oxides
Thallium
Superlattices
Material films
Oxygen
Charge carriers
Materials
Current density
Chemistry
Superconductors
Language
English
ISSN
00368075
10959203
Abstract
Nanometer-scale layered structures based on thallium(III) oxide were electrodeposited in a beaker at room temperature by pulsing the applied potential during deposition. The conducting metal oxide samples were superlattices, with layers as thin as 6.7 nanometers. The defect chemistry was a function of the applied overpotential: High overpotentials favored oxygen vacancies, whereas low overpotentials favored cation interstitials. The transition from one defect chemistry to another in this nonequilibrium process occurred in the same potential range (100 to 120 millivolts) in which the rate of the back electron transfer reaction became significant. The epitaxial structures have the high carrier density and low electronic dimensionality of high transition temperature superconductors.