Investigation on the grain boundaries electrical characteristics of perovskite lithium ion conductors by derivative of tanδ approach

Journal Article · Mon Feb 15 00:00:00 EST 2016 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2015.10.025· OSTI ID:22581416

Bohnke, O. ^[1]

---

1. Institut de Recherche en Ingénierie Moléculaire et Matériaux Fonctionnels (FR CNRS 2575), Laboratoire des Oxydes et Fluorures (UMR 6010CNRS), Université du Maine, Avenue O.Messiaen, 72085 Le Mans Cedex 9 (France)

Graphical abstract: Cole–Cole impedance spectra for Li{sub 0.30}La{sub 0.56}TiO{sub 3}-SSR and Li{sub 0.30}La{sub 0.56}TiO{sub 3}-PC at 310 K and for Li{sub 0.30}Ca{sub 0.35}TaO{sub 3}-SSR and Li{sub 0.30}Ca{sub 0.35}TaO{sub 3}-PC at 473 K. - Highlights: • Li{sub 0.30}La{sub 0.56}TiO{sub 3} & Li{sub 0.30}Ca{sub 0.35}TaO{sub 3} perovskites made by Pechini polymerization route. • Relaxation processes of perovskites are analyzed by derivative of tanδ (α{sub θ}) method. • α{sub θ} (ν) graph resolves the two closer relaxation processes at grain boundary region. • SEM/TEM study supports the resolving ability of α{sub θ} vs log (ν) method. • χ{sup 2} improves from ∼10{sup −3} to ∼10{sup −5} for equivalent circuit fitting based on α{sub θ} peaks. - Abstract: We report on the grain boundaries electrical relaxation processes of Li{sub 0.30}La{sub 0.56}TiO{sub 3} and Li{sub 0.30}Ca{sub 0.35}TaO{sub 3} perovskites by derivative of the tanδ (α{sub θ}) method. The α{sub θ} vs log(ν) representation is clearly resolved the two grain boundary relaxation processes at grain boundary region for perovskites synthesized via the modified Pechini-type polymerization complex route in comparison to perovskites obtained by solid state reaction method. The resolving ability of α{sub θ} vs log(ν) representation is much higher than other complex impedance spectroscopic representations. The goodness of the fitting χ{sup 2} is improved from ∼10{sup −3} to ∼10{sup −5} for the electrical equivalent circuit fitting based on α{sub θ} vs log(ν) peaks.

• OSTI ID: 22581416
• Journal Information: Materials Research Bulletin, Vol. 74; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL STRUCTURE
GRAIN BOUNDARIES
IMPEDANCE
IONIC CONDUCTIVITY
LANTHANUM COMPOUNDS
LITHIUM
LITHIUM COMPOUNDS
LITHIUM IONS
PEROVSKITE
POLYMERIZATION
RELAXATION
SCANNING ELECTRON MICROSCOPY
SPECTROSCOPY
SYNTHESIS
TANTALATES
TEMPERATURE DEPENDENCE
TITANATES
TRANSMISSION ELECTRON MICROSCOPY