Tailoring the properties of dense yttrium‐doped barium zirconate ceramics with nickel oxide additives by manipulation of the sintering profile

International Journal of Energy ResearchEarly View SPECIAL ISSUE RESEARCH ARTICLE Tailoring the properties of dense yttrium-doped barium zirconate ceramics with nickel oxide additives by manipulation of the sintering profile Zinaida Shakel, Zinaida Shakel Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorFrancisco J. A. Loureiro, Francisco J. A. Loureiro orcid.org/0000-0002-5050-3859 Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorIsabel Antunes, Isabel Antunes Department of Materials and Ceramic Engineering, CICECO, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorSergey M. Mikhalev, Sergey M. Mikhalev Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorDuncan P. Fagg, Corresponding Author Duncan P. Fagg duncan@ua.pt orcid.org/0000-0001-6287-9223 Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, Portugal Correspondence Duncan P. Fagg, Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro 3810-193, Portugal. Email: duncan@ua.ptSearch for more papers by this author Zinaida Shakel, Zinaida Shakel Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorFrancisco J. A. Loureiro, Francisco J. A. Loureiro orcid.org/0000-0002-5050-3859 Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorIsabel Antunes, Isabel Antunes Department of Materials and Ceramic Engineering, CICECO, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorSergey M. Mikhalev, Sergey M. Mikhalev Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, PortugalSearch for more papers by this authorDuncan P. Fagg, Corresponding Author Duncan P. Fagg duncan@ua.pt orcid.org/0000-0001-6287-9223 Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro, Portugal Correspondence Duncan P. Fagg, Centre for Mechanical Technology and Automation, Mechanical Engineering Department, University of Aveiro, Aveiro 3810-193, Portugal. Email: duncan@ua.ptSearch for more papers by this author First published: 16 July 2022 https://doi.org/10.1002/er.8389 Funding information: Agência Nacional de Inovação, Grant/Award Number: POCI-01-0247-FEDER-039926; Fundação para a Ciência e a Tecnologia, Grant/Award Numbers: CEECIND/02797/2020, POCI-01-0145-FEDER-032241, PTDC/CTM-CTM/2156/2020, PTDC/QUI-ELT/3681/2020, UIDB/00481/2020, UIDP/00481/2020; Fundo Regional para a Ciência e Tecnologia, Grant/Award Number: CENTRO-01-0145-FEDER-022083; European Regional Development Fund Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Summary Liquid phase sintering (LPS), by the addition of transition metal additives, has become one of the most preferred approaches to lower the sintering temperature of yttrium-doped barium zirconate (BZY) proton-conducting ceramics. Nonetheless, this approach is known to negatively impact the bulk conductivity of the parent perovskite phase, due to the significant incorporation of the sintering additive into the bulk composition. In the current work, we study the typical proton conducting material BaZr0.8Y0.2O3−δ (BZY20), prepared by One or Two-step sintering strategies using 4 mol% NiO of sintering additive, compared against a control sample of pure BZY20. The main results demonstrate that the Two-step approach is shown to minimise Ni interreaction with the BZY material, allowing this sample to maintain a higher hydration capacity than the One-step material, as confirmed by X-ray diffraction (XRD), scanning transmission electron microscopy/energy-dispersive spectrocopy (STEM/EDS) and thermogravimetric (TG) measurements. Despite these benefits, the Two-step approach presents a diminished bulk conductivity, which was ascribed to depletions in proton mobility due to “proton trapping” effects. In addition, the specific grain boundary conductivity was revealed to be higher in the Two-step sample, as a possible result of a higher Ni accumulation in this region. Overall, this work opens an exciting new debate for further studies, in that prevention of Ni-incorporation in the bulk material, as typically suggested in current literature, may not actually be the best method to improve the conductivity of samples densified by Ni-additives and that control of potential defect associations may be the more critical method for conductivity tailoring. Open Research DATA AVAILABILITY STATEMENT The data that support the findings of this study are available from the corresponding authors upon reasonable request. Supporting Information Filename Description er8389-sup-0001-FigureS1.pdfPDF document, 427.2 KB Figure S1 Example of Rietveld refinement for the Two-step sample. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. 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