The microstructural reconstruction of variously sintered Ni-SDC cermets using focused ion beam scanning electron microscopy nanotomography

Kapun, Gregor (author), Majorovits, Endre (author), Šturm, Sašo (author), Marinšek, Marjan (author), Skalar, Tina (author)

This work focuses in-depth on the quantitative relationships between primary first-order microstructural parameters (i.e., volume fractions of various phases and particle size distribution) with the more complex second-order topological features (i.e., connectivity of phases, three-phase boundary length (TPB$_L$), interfacial areas, or tortuosity). As a suitable model material, a cermet nickel/samaria-doped ceria (Ni-SDC) is used as an anode in a solid oxide fuel cell (SOFC). A microstructure description of nano-sized Ni-SDC cermets, fabricated at various sintering conditions from 1100 °C to 1400 °C, was performed using FIB-SEM nanotomography. The samples were serially sectioned employing a fully automated slicing procedure with active drift correction algorithms and an auto-focusing routine to obtain a series of low-loss BSE images. Advanced image processing algorithms were developed and applied directly to image data volume. The microstructural–topological relationships are crucial for the microstructure optimisation and, thus, the improvement of the corresponding electrode performance. Since all grains of individual phases (Ni, SDC, or pores) did not percolate, special attention was given to the visualisation of the so-called active TPB$_L$. Based on the determined microstructure characteristics of the prepared Ni-SDC cermets, including simulations of gas flow and pressure drop, thermal treatment at 1200 °C was recognised as the most appropriate sintering temperature.

• Language: English
• Keywords: solide oxide fuel cells, cermets, focused ion beam scanning electron microscopy, microstructure, morphology
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology; NTF - Faculty of Natural Sciences and Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: 19 str.
• Numbering: Vol. 17, iss. 13, [art.] 3068
• PID: 20.500.12556/RUL-158978
• UDC: 620.1:621.352
• ISSN on article: 1996-1944
• DOI: 10.3390/ma17133068
• COBISS.SI-ID: 199842819
• Publication date in RUL: 26.06.2024

Record is a part of a journal

• Title: Materials
• Shortened title: Materials
• Publisher: Molecular Diversity Preservation International
• ISSN: 1996-1944
• COBISS.SI-ID: 33588485

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: gorivne celice s trdnim elektrolitom, kermeti, vrstični elektronski mikroskop s tehnologijo fokusiranega ionskega sklopa, mikrostruktura, morfologija