Dual luminescent and magnetic properties in Ti1-xNdxO2-δ solid solutions with nanoscaled rutile

Colomer, María T. ; Quesada, A. ; López-Sánchez, J. ; Martínez Martínez, Jesús Ignacio (Universidad de Zaragoza) ; Mather, G.C. ; Molina, P.

Resumen: In this work, we have synthesised Ti1-xNdxO2-0.5x solid solutions (0.05 ≤ x ≤ 0.10) by a colloidal sol−gel route followed by calcination at 400, 700 or 900 °C in air for 10 min. Pure rutile solid solutions were obtained when calcined at 900 °C for compositions up to 1 mol% Nd3+. On doping with 2, 3, 5, and 10 mol% Nd3+, the solid solutions are comprised of rutile and Nd4Ti9O24 as second phase according to XRD. In addition, by HREM TiO1.9 Magneli series is also observed as a trace. Photoluminescence (PL) decay curves show a multi−exponential decay behaviour likely attributable to the structural properties of the host matrix and the formation of at least two different microenvironments. Moreover, to the best of our knowledge, it is shown for the first time that, in addition to PL emission, rutile solid solutions with x = 0.03 present ferromagnetic behaviour with a robust magnetic hysteresis. According to the magnetisation measurements, the isolated Nd3+ centres, detected by EPR, are magnetically non−interacting; in addition, Nd4Ti9O24 presents a paramagnetic behaviour. Furthermore, the height of the EPR feature increases for Nd3+ content below 3 mol%, reaches a maximum for this value, and decreases for higher values of Nd3+. In this framework, a plausible explanation is that a non−stoichiometric Nd−Ti−O based phase, undetectable via XRD or Raman but detectable by PL and magnetisation measurements, hosts the magnetic order. These results pave the way for the development of novel optomagnetic multifunctional nanomaterials.

Idioma: Inglés

DOI: 10.1016/j.ceramint.2025.08.154

Año: 2025

Publicado en: Ceramics International 51, 26 (2025), 49079-49090
ISSN: 0272-8842

Financiación: info:eu-repo/grantAgreement/ES/AEI/AEI PID2022-140923NB-C21
Financiación: info:eu-repo/grantAgreement/ES/MICINN/PID2019-104118RB-C21
Financiación: info:eu-repo/grantAgreement/EUR/MICINN/TED2021-130809B-I00
Financiación: info:eu-repo/grantAgreement/EUR/MICINN/TED2021-130957B-C51
Financiación: info:eu-repo/grantAgreement/ES/MICIU/CNS2022-135876
Financiación: info:eu-repo/grantAgreement/ES/MICIU/PID2021-124585NB-C33

Tipo y forma: Article (Published version)

Área (Departamento): Área Física Materia Condensada (Dpto. Física Materia Condensa.)