{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T06:22:59Z","timestamp":1768458179499,"version":"3.49.0"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,9,21]],"date-time":"2022-09-21T00:00:00Z","timestamp":1663718400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micro"],"abstract":"<jats:p>In this work, orthorhombic (\u03b1-BiNbO4) and triclinic bismuth niobate (\u03b2-BiNbO4) ceramics were prepared by a wet chemical route. The structure of the obtained powders was characterised by X-ray diffraction and the morphology by scanning electron microscopy. The dielectric measurements were performed in the radiofrequency region, at different temperatures, using the impedance spectroscopy technique. The \u03b1-BiNbO4 sample presented a temperature-dependent relaxation process, with the corresponding activation energy being calculated through the Arrhenius equation. The AC conductivity dependence on the frequency was in agreement with Jonscher\u2019s universal power. The conduction mechanism in the \u03b1-BiNbO4 compound is governed by two processes, which can be ascribed to a hopping transport mechanism. The correlated barrier hopping model until 280 K and the non-overlapping small polaron tunnelling model above 280 K are the most suitable models to describe the conductivity of this sample. In the \u03b2-BiNbO4 compound, the motion of mobile charge carriers involves localised hopping between neighbouring sites.<\/jats:p>","DOI":"10.3390\/micro2040036","type":"journal-article","created":{"date-parts":[[2022,9,22]],"date-time":"2022-09-22T01:47:06Z","timestamp":1663811226000},"page":"549-563","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Dielectric Behaviour and Electrical Conductivity of \u03b1-BiNbO4 and \u03b2-BiNbO4 Ceramics"],"prefix":"10.3390","volume":"2","author":[{"given":"S.","family":"Devesa","sequence":"first","affiliation":[{"name":"CFisUC, Physics Department, University of Coimbra, Rua Larga, 3004-516 Coimbra, Portugal"},{"name":"I3N and Physics Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"M. P.","family":"Gra\u00e7a","sequence":"additional","affiliation":[{"name":"I3N and Physics Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7666-4741","authenticated-orcid":false,"given":"L. C.","family":"Costa","sequence":"additional","affiliation":[{"name":"I3N and Physics Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"9103","DOI":"10.1039\/C8RA00037A","article-title":"Electrical conductivity and dielectric behaviour of nanocrystalline La0.6Gd0.1Sr0.3Mn0.75Si0.25O3","volume":"8","author":"Dhahri","year":"2018","journal-title":"RSC Adv."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2668","DOI":"10.1021\/cm100173p","article-title":"Synthesis and Crystal Structure of Lanthanide Orthoniobates Studied by Vibrational Spectroscopy","volume":"22","author":"Siqueira","year":"2010","journal-title":"Chem. 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