INVESTIGADORES
PELLEGRI Nora Susana
artículos
Título:
Simple and Rapid Fabrication of Na0.5K0.5NbO3 Thin Films by a Chelate Route
Autor/es:
A. FERNÁNDEZ SOLARTE; N. PELLEGRI, ; O. DE SANCTIS; M. G. STACHIOTTI
Revista:
Journal of Ceramics
Editorial:
Hindawi Publishing Corporation
Referencias:
Lugar: New York; Año: 2013 vol. 2013 p. 1 - 7
ISSN:
2090-8644
Resumen:
Na0.5K0.5NbO3 (NKN) thin films were prepared by a chelate route which offers the advantage of a simple and rapid solution
synthesis. The route is based on the use of acetoin as a chelating agent. The process was optimized by investigating the effects of
alkaline volatilization on film properties.While we observed no evidence of stoichiometry problems due to potassiumvolatilization
loss during the heat treatments, thin films synthesized with insufficient sodium excess presented a potassium-rich secondary
phase, which has a significant influence on the ferroelectric properties. We show that the amount of spurious phase decreases
with increasing Na+ concentration, in such a way that a 20mol% Na+ excess is necessary to fully compensate the volatilization loss
that occurred during the heat treatment. In this way, NKN thin films annealed at 650∘C presented a well-crystallized perovskite
structure, no secondary phases, well-defined ferroelectric hysteresis loops (𝑃𝑟 ∼ 9𝜇C/cm2, 𝐸𝐶 ∼ 45 kV/cm), and low leakage
current density (2 × 10
−7 A/cm2 at 80 kV/cm).