Accession Number : AD0776584

Title :   Diffusion of Hydrogen and Deuterium in Rutile.

Descriptive Note : Doctoral thesis,

Corporate Author : UTAH UNIV SALT LAKE CITY DIV OF MATERIALS SCIENCE AND ENGINEERING

Personal Author(s) : Paek,Su-Hyon

Report Date : 04 MAY 1974

Pagination or Media Count : 72

Abstract : The effect of internal electric fields, due to changing concentration of a diffusing ion, on the measured diffusion rate is considered. It is shown that the effect of such fields can completely dominate the diffusion process in a material like TiO2, leading to dramatic departures from Fick's law. An isotope exchange technique is described, which almost completely suppresses the internal fields and hence permits accurate determination of the real diffusion parameters. This technique has been applied to the diffusion of H and D in TiO2 and accurate values of all diffusion parameters for diffusion parallel and perpendicular to the c-axis have been obtained. The diffusion appears to be a simple thermally activated process over a wide range of temperatures, with activation energies of 0.59 and 1.28 eV, for diffusion parallel and perpendicular to the c-axis, respectively. Large departures from Fick's law behavior for single diffusion have also been demonstrated. (Author)

Descriptors :   *Diffusion, *Rutile, *Hydrogen, *Deuterium, Temperature, Electric fields, Impurities, Crystal structure, Bonding, Theses

Subject Categories : Physical Chemistry
      Ceramics, Refractories and Glass

Distribution Statement : APPROVED FOR PUBLIC RELEASE