INVESTIGADORES
TAYLOR Marcela Andrea
artículos
Título:
Nanostructures in calcia stabilized hafnia thin films observed by PAC as a function of temperature.
Autor/es:
M.C. CARACOCHE, J.A. MARTINEZ, P.C. RIVAS, M.A. TAYLOR, A.F. PASQUEVICH, S. BAROLIN, O. DE SANCTIS
Revista:
HYPERFINE INTERACTIONS
Editorial:
Springer
Referencias:
Año: 2007 vol. 179 p. 87 - 93
ISSN:
0304-3843
Resumen:
The hyperfine quadrupole interaction at Hf sites in films and powders of 114 mol% CaOHfO2 and 20 mol% CaOHfO2 has been determined as a function 2of temperature. Results indicate the formation of a cubic solid solution and other 3microstructures assigned to the φ1 (CaHf4O9) and φ2 (Ca6Hf19O44) phases. Dynam- 4ical effects on the electric field gradient reveal the existence of oxygen vacancies 5movements in the solid solution. The thermal behavior of the relaxation constant 6observed in films allowed the determination of activation energies of 0.54 eV and 70.70 eV for the 14 mol% and 20 mol% CaO doped hafnias, respectively. The 8influence of the microdomains and the stability of the cubic solid solution are 9discussed.
