{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,31]],"date-time":"2025-12-31T11:56:21Z","timestamp":1767182181711,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2024,10,20]],"date-time":"2024-10-20T00:00:00Z","timestamp":1729382400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FCT","award":["UIDB\/00285\/2020","LA\/P\/0112\/2020","LA\/P\/0037\/2020","UIDP\/50025\/2020","UIDB\/50025\/2020","UIDB\/04968\/2020","UIDP\/04968\/2020","PTDC\/EME-TED\/3099\/2020","PTDC\/FISMAC\/31302\/2017","CERN\/FISTEC\/0003\/2019","SFRH-BPD-87430\/2012"],"award-info":[{"award-number":["UIDB\/00285\/2020","LA\/P\/0112\/2020","LA\/P\/0037\/2020","UIDP\/50025\/2020","UIDB\/50025\/2020","UIDB\/04968\/2020","UIDP\/04968\/2020","PTDC\/EME-TED\/3099\/2020","PTDC\/FISMAC\/31302\/2017","CERN\/FISTEC\/0003\/2019","SFRH-BPD-87430\/2012"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Magnetochemistry"],"abstract":"<jats:p>Recent research in solid-state physics and materials engineering focuses on the development of new dielectric materials, with bismuth-based pyrochlores being already extensively applied in communications technology for their excellent dielectric properties and relatively low sintering temperatures. Herein, the structural, morphological, electrical, and magnetic properties of Bi1.34Fe0.66Nb1.34O6.35 ceramic, prepared by the sol\u2013gel method and sintered at 500 \u00b0C, are investigated. The Rietveld refinement of the XRD pattern showed a cubic phase belonging to the space group Fd-3m and a crystallite size of 42 nm. Transmission electron microscopy further confirmed the crystallite size and the homogeneous distribution of Bi, Fe, Nb, and O elements, as evidenced by high-angle annular dark field imaging and STEM-EDX mapping. The morphology of the sample, assessed by scanning electron microscopy, is characterized by submicron-sized spherical particles. Dielectric spectroscopic studies revealed that the dielectric properties, strongly influenced by frequency and temperature, indicate the material\u2019s potential for energy storage due to lower dielectric loss compared to the dielectric constant. The observed relaxation phenomena, confirmed through variations in dielectric loss and loss tangent, highlight the influence of grain boundaries and temperature on electron hopping and charge carrier dynamics. Using SQUID magnetometry, we identified two distinct magnetic phases. The primary phase, corresponding to the Bi1.34Fe0.66Nb1.34O6.35 ceramic, exhibits an antiferromagnetic behavior below its N\u00e9el temperature at around 8.8 K. A secondary high-Curie temperature ferrimagnetic phase, likely vestigial maghemite and\/or magnetite, was also detected, indicating an estimated fraction below 0.02 wt.%.<\/jats:p>","DOI":"10.3390\/magnetochemistry10100079","type":"journal-article","created":{"date-parts":[[2024,10,21]],"date-time":"2024-10-21T10:49:22Z","timestamp":1729507762000},"page":"79","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Comprehensive Characterization of Bi1.34Fe0.66Nb1.34O6.35 Ceramics: Structural, Morphological, Electrical, and Magnetic Properties"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2217-4584","authenticated-orcid":false,"given":"Susana","family":"Devesa","sequence":"first","affiliation":[{"name":"University of Coimbra, CEMMPRE, ARISE, Department of Mechanical Engineering, Rua Lu\u00eds Reis Santos, 3030-788 Coimbra, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4148-4374","authenticated-orcid":false,"given":"Carlos Oliveira","family":"Amorim","sequence":"additional","affiliation":[{"name":"University of Aveiro, Physics Department and i3N, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"given":"Jo\u00e3o Horta","family":"Belo","sequence":"additional","affiliation":[{"name":"Institute of Physics of Advanced Materials, Nanotechnology and Photonics (IFIMUP), Department of Physics and Astronomy, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1646-7727","authenticated-orcid":false,"given":"Jo\u00e3o P.","family":"Ara\u00fajo","sequence":"additional","affiliation":[{"name":"Institute of Physics of Advanced Materials, Nanotechnology and Photonics (IFIMUP), Department of Physics and Astronomy, Faculty of Sciences, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4084-5764","authenticated-orcid":false,"given":"S\u00edlvia Soreto","family":"Teixeira","sequence":"additional","affiliation":[{"name":"University of Aveiro, Physics Department and i3N, Campus Universit\u00e1rio de Santiago, 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":"University of Aveiro, Physics Department and i3N, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7666-4741","authenticated-orcid":false,"given":"Lu\u00eds Cadillon","family":"Costa","sequence":"additional","affiliation":[{"name":"University of Aveiro, Physics Department and i3N, Campus Universit\u00e1rio de Santiago, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,10,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"840","DOI":"10.1016\/j.jre.2020.01.002","article-title":"A2B2O7 Pyrochlore Compounds: A Category of Potential Materials for Clean Energy and Environment Protection Catalysis","volume":"38","author":"Xu","year":"2020","journal-title":"J. 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