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Y. Kharchenko et al.
consisted of Ni fringes and “bridges.” Finally, the specific electrical conductivity of
the material increased along with its strength.
The trend of changes in the characteristics of relative stiffness (107%) and strength
(192%) during redox treatment differs absolutely from those obtained for one-time
reduced material (see Table 1). This peculiarity shows the efficiency of the proposed
technique in providing the established levels of the physical and mechanical characteristics of the YSZ–NiO and ScCeSZ–NiO materials for manufacturing SOFC
anodes.
4 Conclusions
In this work, after applying of the developed redox treatment mode, the following
micro- and nanostructural changes in the as-sintered NiO ceramics were found:
a network of nanopores was formed in the external layer of particles of the nickel
phase; thin pieces of reduced Ni subgrains were separated causing a reduction in the
size of particles of Ni-phase; tiny Ni pieces were coagulated causing partial reduction
of the porosity and formation of “bridges”; the initial particles of the nickel phase were
united in clusters with the formation of nanopores at the sites of former boundaries;
and a nickel network was formed that consisted of Ni fringes and “bridges.” All
these changes allow providing the required mechanical and physical properties of
the Ni/NiO cermet. The authors suggest such treatment technique be applicable for
the YSZ–NiO and ScCeSZ–NiO anode materials while manufacturing SOFCs.
References
1. Thydén K (2008) Microstructural degradation of Ni-YSZ anodes for solid oxide fuel cells.
Ph.D. thesis, Technical University of Denmark, Roskilde, Denmark
2. Simwonis D, Tietz F, Stoever D (2000) Nickel coarsening in annealed Ni/8YSZ anode substrates
for solid oxide fuel cells. Solid State Ionics 132:241–251
3. Vassen R, Simwonis D, Stoever D (2001) Modelling of the agglomeration of Ni-particles in
anodes of solid oxide fuel cells. J Mater Sci 36:147–151
4. Van Herle J, Larrain D, Autissier N et al (2005) Modeling and experimental validation of solid
oxide fuel cell materials and stacks. J Eur Ceram Soc 25:2627–2632
5. Wuillemin Z, Autissier N, Van Herle J et al (2005) Modeling and study of the influence of
sealing on a solid oxide fuel cell. In: Proceedings of the 1st European fuel cell technology and
applications conference, Rome, Italy, 14–16 Dec 2005
6. Steele BCH, Heinzel A (2001) Materials for fuel-cell technologies. Nature 414:345–352
7. Faes A, Hessler-Wyser A, Zryd A et al (2012) A review of RedOx cycling of solid oxide fuel
cells anode. Membranes 2(3):585–664. https://doi.org/10.3390/membranes2030585
8. Railsback JG, Johnston-Peck AC, Wang J et al (2010) Size-dependent nanoscale Kirkendall
effect during the oxidation of nickel nanoparticles. ACS Nano 4:1913–1920
9. Gmelin L (1968) Gmelin handbook of inorganic chemistry, 8th edn. Springer, Berlin
10. Karmhag R, Niklasson GA, Nygren M (1999) Oxidation kinetics of large nickel particles. J
Mater Res 14:3051–3058
Y. Kharchenko et al.
consisted of Ni fringes and “bridges.” Finally, the specific electrical conductivity of
the material increased along with its strength.
The trend of changes in the characteristics of relative stiffness (107%) and strength
(192%) during redox treatment differs absolutely from those obtained for one-time
reduced material (see Table 1). This peculiarity shows the efficiency of the proposed
technique in providing the established levels of the physical and mechanical characteristics of the YSZ–NiO and ScCeSZ–NiO materials for manufacturing SOFC
anodes.
4 Conclusions
In this work, after applying of the developed redox treatment mode, the following
micro- and nanostructural changes in the as-sintered NiO ceramics were found:
a network of nanopores was formed in the external layer of particles of the nickel
phase; thin pieces of reduced Ni subgrains were separated causing a reduction in the
size of particles of Ni-phase; tiny Ni pieces were coagulated causing partial reduction
of the porosity and formation of “bridges”; the initial particles of the nickel phase were
united in clusters with the formation of nanopores at the sites of former boundaries;
and a nickel network was formed that consisted of Ni fringes and “bridges.” All
these changes allow providing the required mechanical and physical properties of
the Ni/NiO cermet. The authors suggest such treatment technique be applicable for
the YSZ–NiO and ScCeSZ–NiO anode materials while manufacturing SOFCs.
References
1. Thydén K (2008) Microstructural degradation of Ni-YSZ anodes for solid oxide fuel cells.
Ph.D. thesis, Technical University of Denmark, Roskilde, Denmark
2. Simwonis D, Tietz F, Stoever D (2000) Nickel coarsening in annealed Ni/8YSZ anode substrates
for solid oxide fuel cells. Solid State Ionics 132:241–251
3. Vassen R, Simwonis D, Stoever D (2001) Modelling of the agglomeration of Ni-particles in
anodes of solid oxide fuel cells. J Mater Sci 36:147–151
4. Van Herle J, Larrain D, Autissier N et al (2005) Modeling and experimental validation of solid
oxide fuel cell materials and stacks. J Eur Ceram Soc 25:2627–2632
5. Wuillemin Z, Autissier N, Van Herle J et al (2005) Modeling and study of the influence of
sealing on a solid oxide fuel cell. In: Proceedings of the 1st European fuel cell technology and
applications conference, Rome, Italy, 14–16 Dec 2005
6. Steele BCH, Heinzel A (2001) Materials for fuel-cell technologies. Nature 414:345–352
7. Faes A, Hessler-Wyser A, Zryd A et al (2012) A review of RedOx cycling of solid oxide fuel
cells anode. Membranes 2(3):585–664. https://doi.org/10.3390/membranes2030585
8. Railsback JG, Johnston-Peck AC, Wang J et al (2010) Size-dependent nanoscale Kirkendall
effect during the oxidation of nickel nanoparticles. ACS Nano 4:1913–1920
9. Gmelin L (1968) Gmelin handbook of inorganic chemistry, 8th edn. Springer, Berlin
10. Karmhag R, Niklasson GA, Nygren M (1999) Oxidation kinetics of large nickel particles. J
Mater Res 14:3051–3058