The role of defects in microwave and conventionally synthesized LaCoO3 perovskite

In this work we investigate the magnetic, dielectric and charge transport properties of LaCoO3 (LCO) synthesized by two different techniques: microwave assisted and conventionally heated ceramic synthesis. The rapid microwave synthesis conditions are far away from thermodynamic equilibrium and are f...

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Detalles Bibliográficos
Autores: Prado Gonjal, Jesús de la Paz, Gutiérrez-Seijas, Julia, Herrero Ansorregui, Irene, Morán Miguélez, Emilio, Terry, Ian, Schmidt, Rainer
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/92291
Acceso en línea:https://hdl.handle.net/20.500.14352/92291
Access Level:acceso abierto
Palabra clave:546
Microwave synthesis
LaCoO3
Magnetism
Impedance spectroscopy
Química inorgánica (Química)
Física (Física)
2303 Química Inorgánica
2210.28 Química del Estado Sólido
Descripción
Sumario:In this work we investigate the magnetic, dielectric and charge transport properties of LaCoO3 (LCO) synthesized by two different techniques: microwave assisted and conventionally heated ceramic synthesis. The rapid microwave synthesis conditions are far away from thermodynamic equilibrium and are found to lead to modified crystal defect properties as compared to conventional synthesis. The thermally induced magnetic spin state transition at Ts1 ≈ 80 K is exemplified by temperature (T)-dependent dielectric spectroscopy data, which reveal the appearance of an additional dielectric contribution that is correlated to the transition. Magnetisation, M vs T, and electrical resistivity, ρ vs T, curves show that the additional dielectric phase is strongly influenced by magnetic defects and may be associated with higher spin state clusters in a magnetic spin-state coexistence scenario. We suggest that defects such as oxygen vacancies act as magnetic nucleation centres across the spin state transition Ts1 for the formation of higher spin state clusters in LCO perovskites.