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. 2021 Aug 5;11(8):2004.
doi: 10.3390/nano11082004.

An Interface Heterostructure of NiO and CeO2 for Using Electrolytes of Low-Temperature Solid Oxide Fuel Cells

Junjiao Li  1 , Jun Xie  2 , Dongchen Li  3 , Lei Yu  4 , Chaowei Xu  2 , Senlin Yan  2 , Yuzheng Lu  2
Affiliations

An Interface Heterostructure of NiO and CeO2 for Using Electrolytes of Low-Temperature Solid Oxide Fuel Cells

Junjiao Li et al. Nanomaterials (Basel). .

Abstract

Interface engineering can be used to tune the properties of heterostructure materials at an atomic level, yielding exceptional final physical properties. In this work, we synthesized a heterostructure of a p-type semiconductor (NiO) and an n-type semiconductor (CeO2) for solid oxide fuel cell electrolytes. The CeO2-NiO heterostructure exhibited high ionic conductivity of 0.2 S cm-1 at 530 °C, which was further improved to 0.29 S cm-1 by the introduction of Na+ ions. When it was applied in the fuel cell, an excellent power density of 571 mW cm-1 was obtained, indicating that the CeO2-NiO heterostructure can provide favorable electrolyte functionality. The prepared CeO2-NiO heterostructures possessed both proton and oxygen ionic conductivities, with oxygen ionic conductivity dominating the fuel cell reaction. Further investigations in terms of electrical conductivity and electrode polarization, a proton and oxygen ionic co-conducting mechanism, and a mechanism for blocking electron transport showed that the reconstruction of the energy band at the interfaces was responsible for the enhanced ionic conductivity and cell power output. This work presents a new methodology and scientific understanding of semiconductor-based heterostructures for advanced ceramic fuel cells.

Keywords: band structure; built-in field; interface heterostructure; ionic conduction; low-temperature solid oxide fuel cells; nanomaterials.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
XRD patterns for the prepared CeO2-NiO and CeO2-Na-NiO.
Figure 2
Figure 2
SEM images of (a) commercial CeO2; (b) CeO2-NiO; (c) CeO2-Na-NiO; (d) the cross-sectional SEM graph of CeO2-Na-NiO.
Figure 3
Figure 3
(a) TEM and (b) HRTEM images of CeO2-Na-NiO, with the inset in (b) giving the fast Fourier transform of corresponding HRTEM; (c) HAADF-TEM image and corresponding EDS maps of CeO2-Na-NiO for (d) Ni, (e) Ce, and (f) O.
Figure 3
Figure 3
(a) TEM and (b) HRTEM images of CeO2-Na-NiO, with the inset in (b) giving the fast Fourier transform of corresponding HRTEM; (c) HAADF-TEM image and corresponding EDS maps of CeO2-Na-NiO for (d) Ni, (e) Ce, and (f) O.
Figure 4
Figure 4
(a) XPS spectra of as-prepared CeO2-NiO and CeO2-Na-NiO, corresponding to survey scan, (b) Ce 3d spectrum, (c) Ni 2p spectrum, and (d) O 1s spectrum.
Figure 5
Figure 5
(a) Electrochemical performance of the fuel cells with CeO2-NiO and CeO2-Na-NiO at 530 °C; (b) EIS of Figure 2. NiO and CeO2-Na-NiO at 530 °C.
Figure 6
Figure 6
Electrochemical performance of the fuel cells with pure CeO2 and NiO at 530 °C.
Figure 7
Figure 7
(a) Electrochemical performance of the fuel cells with only proton conductivity using BZCY at 530 °C; (b) the “proton shuttles” transport in the high-conducting region of the electrolyte membrane constituted by the interface heterostructure of CeO2-NiO; (c) charge separation at the interface of CeO2-NiO particle.
Figure 7
Figure 7
(a) Electrochemical performance of the fuel cells with only proton conductivity using BZCY at 530 °C; (b) the “proton shuttles” transport in the high-conducting region of the electrolyte membrane constituted by the interface heterostructure of CeO2-NiO; (c) charge separation at the interface of CeO2-NiO particle.
Figure 8
Figure 8
The band structure of CeO2-NiO heterostructure composites.
Figure 9
Figure 9
(a) the I−V characteristics under the bias measurements of the CeO2-Na-NiO heterostructure in air/air and in H2/air environments, and (b) the durability test result of the CeO2-Na-NiO sample at current density of 0.1 A cm−2 at 530 °C.
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References

    1. Duan C.C., Tong J.H., Shang M., Nikodemski S.F., Sanders M., Ricote S. Almans. Readily processed protonic ceramic fuel cells with high performance at low temperatures. Science. 2020;349:1321–1326. doi: 10.1126/science.aab3987. - DOI - PubMed
    1. Ni M., Shao Z.P. Fuel cells that operate at 300 to 500 °C. Science. 2020;369:138–139. doi: 10.1126/science.abc9136. - DOI - PubMed
    1. Simwonis D., Tietz F., Stöver D. Nickel coarsening in annealed Ni/8YSZ anode substrates for solid oxide fuel cells—In memoriam to Professor H. Tagawa. Solid State Ionics. 2000;132:241–245. doi: 10.1016/S0167-2738(00)00650-0. - DOI
    1. Faes A., Hessler-Wyser A., Presvytes D., Vayenas C.G., Vanherle J. Nickel-Zirconia Anode Degradation and Triple Phase Boundary Quantification from Microstructural Analysis. Fuel Cells. 2009;9:841–844. doi: 10.1002/fuce.200800147. - DOI
    1. Fang Q., Blum L., Batfalsky P., Menzler N.H., Packbier U., Stolten D. Durability test and degradation behavior of a 2.5 kW SOFC stack with internal reforming of LNG. Int. J. Hydrogen Energy. 2013;38:16344–16353. doi: 10.1016/j.ijhydene.2013.09.140. - DOI

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