{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T17:25:58Z","timestamp":1770744358378,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2019,6,26]],"date-time":"2019-06-26T00:00:00Z","timestamp":1561507200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["SFRH\/BPD\/124238\/2016"],"award-info":[{"award-number":["SFRH\/BPD\/124238\/2016"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["project of bilateral cooperation between FCT and DAAD (Germany)"],"award-info":[{"award-number":["project of bilateral cooperation between FCT and DAAD (Germany)"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"name":"COMPETE 2020 Program and National Funds through the FCT\/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement","award":["UID\/CTM\/50011\/2019"],"award-info":[{"award-number":["UID\/CTM\/50011\/2019"]}]},{"name":"COMPETE 2020 Program and National Funds through the FCT\/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement","award":["POCI-01-0145-FEDER-031875"],"award-info":[{"award-number":["POCI-01-0145-FEDER-031875"]}]},{"DOI":"10.13039\/100010665","name":"H2020 Marie Sk\u0142odowska-Curie Actions","doi-asserted-by":"publisher","award":["H2020-MSCA-RISE-2016 SPICOLOST (Grant No. 734187)"],"award-info":[{"award-number":["H2020-MSCA-RISE-2016 SPICOLOST (Grant No. 734187)"]}],"id":[{"id":"10.13039\/100010665","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Portuguese national funds (OE), through FCT, I.P.","award":["contract provided for by numbers 4, 5, and 6 of article 23, of the Decree-Law 57\/2016, of August 29, changed by Law 57\/2017, of July 19"],"award-info":[{"award-number":["contract provided for by numbers 4, 5, and 6 of article 23, of the Decree-Law 57\/2016, of August 29, changed by Law 57\/2017, of July 19"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Zinc oxide (ZnO) has being recognised as a potentially interesting thermoelectric material, allowing flexible tuning of the electrical properties by donor doping. This work focuses on the assessment of tantalum doping effects on the relevant structural, microstructural, optical and thermoelectric properties of ZnO. Processing of the samples with a nominal composition Zn1\u2212xTaxO by conventional solid-state route results in limited solubility of Ta in the wurtzite structure. Electronic doping is accompanied by the formation of other defects and dislocations as a compensation mechanism and simultaneous segregation of ZnTa2O6 at the grain boundaries. Highly defective structure and partial blocking of the grain boundaries suppress the electrical transport, while the evolution of Seebeck coefficient and band gap suggest that the charge carrier concentration continuously increases from x = 0 to 0.008. Thermal conductivity is almost not affected by the tantalum content. The highest ZT~0.07 at 1175 K observed for Zn0.998Ta0.002O is mainly provided by high Seebeck coefficient (\u2212464 \u03bcV\/K) along with a moderate electrical conductivity of ~13 S\/cm. The results suggest that tantalum may represent a suitable dopant for thermoelectric zinc oxide, but this requires the application of specific processing methods and compositional design to enhance the solubility of Ta in wurtzite lattice.<\/jats:p>","DOI":"10.3390\/ma12132057","type":"journal-article","created":{"date-parts":[[2019,6,27]],"date-time":"2019-06-27T02:43:41Z","timestamp":1561603421000},"page":"2057","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Exploring Tantalum as a Potential Dopant to Promote the Thermoelectric Performance of Zinc Oxide"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7449-7553","authenticated-orcid":false,"given":"Blanca I.","family":"Arias-Serrano","sequence":"first","affiliation":[{"name":"CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Wenjie","family":"Xie","sequence":"additional","affiliation":[{"name":"Materials and Resources, Techn, Universit\u00e4t Darmstadt, Alarich-Weiss Str.2, DE-64287 Darmstadt, Germany"}]},{"given":"Myriam H.","family":"Aguirre","sequence":"additional","affiliation":[{"name":"Condensed Matter Physics Department, University of Zaragoza and Institute of Material Science of Arag\u00f3n, ICMA-CSIC, E-50018 Zaragoza, Spain"},{"name":"Advanced Microscopy Laboratory, I+D Building-Campus R\u00edo Ebro, C\/Mariano Esquillor s\/n, 50018 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0112-8570","authenticated-orcid":false,"given":"David M.","family":"Tobaldi","sequence":"additional","affiliation":[{"name":"CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Artur R.","family":"Sarabando","sequence":"additional","affiliation":[{"name":"CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Shahed","family":"Rasekh","sequence":"additional","affiliation":[{"name":"CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"},{"name":"i3N, Physics Department, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Sergey M.","family":"Mikhalev","sequence":"additional","affiliation":[{"name":"TEMA-NRD, Mechanical Engineering Department, Aveiro Institute of Nanotechnology (AIN), University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Jorge R.","family":"Frade","sequence":"additional","affiliation":[{"name":"CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"Anke","family":"Weidenkaff","sequence":"additional","affiliation":[{"name":"Materials and Resources, Techn, Universit\u00e4t Darmstadt, Alarich-Weiss Str.2, DE-64287 Darmstadt, Germany"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5814-9797","authenticated-orcid":false,"given":"Andrei V.","family":"Kovalevsky","sequence":"additional","affiliation":[{"name":"CICECO-Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"105","DOI":"10.1038\/nmat2090","article-title":"Complex thermoelectric materials","volume":"7","author":"Snyder","year":"2008","journal-title":"Nat. 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