{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T03:10:18Z","timestamp":1768619418876,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2024,6,27]],"date-time":"2024-06-27T00:00:00Z","timestamp":1719446400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"i3N","award":["LA\/P\/0037\/2020"],"award-info":[{"award-number":["LA\/P\/0037\/2020"]}]},{"name":"i3N","award":["UID-B\/50025\/2020"],"award-info":[{"award-number":["UID-B\/50025\/2020"]}]},{"name":"i3N","award":["UID-P\/50025\/2020"],"award-info":[{"award-number":["UID-P\/50025\/2020"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["LA\/P\/0037\/2020"],"award-info":[{"award-number":["LA\/P\/0037\/2020"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["UID-B\/50025\/2020"],"award-info":[{"award-number":["UID-B\/50025\/2020"]}]},{"name":"FCT\u2014Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","award":["UID-P\/50025\/2020"],"award-info":[{"award-number":["UID-P\/50025\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Crystals"],"abstract":"<jats:p>This study presents the dielectric properties of a barium titanate\u2013gadolinium ferrite composite material, obtained through a solid-state reaction method. The aim of this research was to create a composite material with enhanced dielectric properties compared to each individual component, and to investigate the electrical properties of the composites, using impedance spectroscopy. The structural and morphologic properties were analyzed using X-ray diffraction and scanning electron microscopy, respectively. Impedance spectroscopy measurements were performed over a wide frequency range (100\u20130.1 GHz) and temperature (45\u2013170 \u00b0C) to evaluate the electrical behavior of the material. The dielectric relaxations were analyzed using the Havriliak\u2013Negami function, and the key electrical parameters such as relaxation frequency, dielectric strength, and electrical conductivity were extracted. Several relaxation processes were identified, which depend on the mixture of the initial titanate and ferrite materials, and a correlation between structural, morphologic, and electrical properties was exposed. The sample with the highest dielectric constant was the 25 wt% gadolinium ferrite composite, with \u03b5\u2032 close to 240 and loss tangent values below 0.1, affording it the more appropriate composition for energy storage devices such as lead-free dielectric capacitors.<\/jats:p>","DOI":"10.3390\/cryst14070590","type":"journal-article","created":{"date-parts":[[2024,6,27]],"date-time":"2024-06-27T08:57:50Z","timestamp":1719478670000},"page":"590","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["BaTiO3\u2014Gd3Fe5O12 Composites: Exploring the Dielectric Properties in a Broad Frequency Range"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6436-7376","authenticated-orcid":false,"given":"Bruno M. G.","family":"Melo","sequence":"first","affiliation":[{"name":"i3N and Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Clara","family":"Baivier","sequence":"additional","affiliation":[{"name":"CNRS, IETR\u2013UMR 6164, University of Rennes, 35000 Rennes, France"}]},{"given":"Ratiba","family":"Benzerga","sequence":"additional","affiliation":[{"name":"CNRS, IETR\u2013UMR 6164, University of Rennes, 35000 Rennes, France"}]},{"given":"Didier","family":"Fasquelle","sequence":"additional","affiliation":[{"name":"UDSMM, Universit\u00e9 du Littoral C\u00f4te d\u2019Opale, 50, Rue Ferdinand Buisson, B.P. 717, 62228 Calais CEDEX, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4084-5764","authenticated-orcid":false,"given":"S. Soreto","family":"Teixeira","sequence":"additional","affiliation":[{"name":"i3N and Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6858-9507","authenticated-orcid":false,"given":"Manuel P. F.","family":"Gra\u00e7a","sequence":"additional","affiliation":[{"name":"i3N and Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7666-4741","authenticated-orcid":false,"given":"Lu\u00eds","family":"Costa","sequence":"additional","affiliation":[{"name":"i3N and Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,6,27]]},"reference":[{"key":"ref_1","first-page":"606","article-title":"Impedance Measurement Techniques and Data Analysis","volume":"Volume 177","author":"Barsoukov","year":"2005","journal-title":"Impedance Spectroscopy Theory, Experiment, and Applications"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Yuan, Y., Lin, J., Wang, X., Qian, J., Zuo, P., and Zhuang, Q. (2023). Achieving Excellent Dielectric and Energy Storage Performance in Core-Double-Shell-Structured Polyetherimide Nanocomposites. 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