RT Journal Article T1 Growth of Zr/ZrO_(2) core-shell structures by fast thermal oxidation A1 Ramos Justicia, Juan Francisco A1 Ballester Andújar, José Luis A1 Urbieta Quiroga, Ana Irene A1 Fernández Sánchez, Paloma AB This research has been conducted to characterize and validate resistive heating as a synthesis method for zirconium oxides (ZrO_(2)). A wire of Zr has been oxidized to form a core-shell structure, in which the core is a metal wire, and the shell is an oxide layer that is around 10 mu m thick. The characterization of the samples has been performed by means of several techniques based on Scanning Electron Microscopy (SEM). The topography images show that thermal gradient appears to have little influence on morphology, unlike time, which plays an important role. The chemical composition was analyzed by X-ray spectroscopy (EDX) and X-ray diffraction (XRD), and Raman spectroscopy has been used to assess crystallinity and crystal structure. The oxide layer is mainly formed by monoclinic ZrO_(2), alongside other, less significant, phases. Photoluminescence (PL) and cathodoluminescence (CL) measurements have allowed us to study the distribution of defects along the shell and to confirm the degree of uniformity. The oxygen vacancies, either as isolated defects or forming complexes with impurities, play a determinant role in the luminescent processes. Color centers, mainly electron centers such as F, F-A and F-AA, give rise to several visible emissions extending from blue to green, with main components at around 2 eV, 2.4-2.5 eV and 2.7 eV. The differences between PL and CL in relation to distinct recombination paths are also discussed. PB MDPI SN 2076-3417 YR 2023 FD 2023-03-14 LK https://hdl.handle.net/20.500.14352/73343 UL https://hdl.handle.net/20.500.14352/73343 LA eng NO © 2023 by the authors. Licensee MDPI,This work has been funded by the Complutense University—Comunidad de Madrid via project PR65/19-22464. NO Comunidad de Madrid / Universidad Complutense de Madrid (UCM) DS Docta Complutense RD 6 abr 2025