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2022 | Book

Oxide-Ion Conduction in the Dion–Jacobson-Type Layered Perovskites

Author: Dr. Wenrui Zhang

Publisher: Springer Nature Singapore

Book Series: Springer Theses

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About this book

This book reports a study of a class of Dion–Jacobson-type layered perovskite oxides in which high oxide-ion conductivities in phases were discovered for the first time in the world. The oxide-ion conductors are important in various energy conversion devices and environmental protection applications such as solid-oxide fuel cells, oxygen gas sensors, oxygen separation membranes, and oxygen-based catalysts. The discoveries are based on a new screening method, called the bond valence method, combined with an original design concept. The present finding of high oxide-ion conductivity reported in the thesis suggested the potential of Dion–Jacobson phases as a platform to identify superior oxide-ion conductors.
To understand what causes such high oxide-ion conductivities in these layered perovskite oxides, the author analyzed their crystal structures at high temperature and described the relationship between oxide-ion conductivities and their crystal structures. A deep understanding of the mechanisms of oxide-ion diffusivity at an atomic level in the Dion–Jacobson phases is clarified.
The discovery of these materials, the new screening method, and the original design concept make possible the realization of many environment-friendly technologies. The findings in this thesis facilitate the possibilities for many novel applications that will help lead to a sustainable future.

Table of Contents

Frontmatter
Chapter 1. Introduction
Abstract
Global environmental issues, energy issues, and resources are the biggest challenges for our society. Durable, clean, and renewable energy devices are essential to global economic growth and human development, which presents a huge challenge. This challenge is made even more difficult due to the environmental threat of global warming, which is mostly caused by the carbon dioxide (CO2) emissions produced from the primary energy sources, such as fossil fuels.
Wenrui Zhang
Chapter 2. New Oxide-Ion Conductors of Dion–Jacobson-Type Layered Perovskites CsBi2Ti2NbO10-δ
Abstract
Oxide-ion conductors exhibit many important applications in many electrochemical devices, for example, solid-oxide fuel cells (SOFCs), solid-oxide electrolysis cell (SOECs), oxygen gas sensors, and oxygen separation membranes. Dion–Jacobson phases have attracted attention because of their wide chemical and physical performances, however, up to now, there are no reports of oxide-ion conductors with the Dion–Jacobson structure. Here, we have reported the new oxide-ion conductors of Dion–Jacobson-type layered perovskites for the first time. The oxide-ion migration energy barriers, Eb, of 69 Dion–Jacobson phases were calculated using 83 Dion–Jacobson-type crystal data, in order to find new oxide-ion conductors in the Dion–Jacobson phases. CsBi2Ti2NbO10−δ was chosen because of its relatively low Eb. The bulk conductivity of CsBi2Ti2NbO10−δ (δ is the oxygen vacancy content) was 8.9 × 10−2 S cm−1 at 1073 K, which was higher than that of the conventional yttria-stabilized zirconia (YSZ). There is a jump in conductivity between 823 and 873 K, which may can be attributed to the high level of oxygen vacancy concentration and the orthorhombic-to-tetragonal phase transition. In order to improve its conductivity, doping elements in the A (Bi site) and B sites (Ti/Nb site) were investigated. The CsBi2−xMxTi2+yNb1–yO10−x/2–y/2-δ (M = alkaline earth metal; x = 0.1, 0.2, 0.3, 0.4, 0.5, and 0.6; y = 0.2, 0.1, −0.1, and −0.2) compounds were synthesized and the electrical properties were investigated. The high conductivity of Dion–Jacobson-type layered perovskites CsBi2Ti2NbO10-δ can be attributable to the large anisotropic thermal motions of oxygen atoms (especially O1 and O2), the existence of carrier (oxygen vacancy in high-temperature ranges) and the formation of an oxide-ion conducing layer with large bottleneck sizes (inner perovskite layers). The present finding of high oxide-ion conductivities in the Dion–Jacobson-type layered perovskites CsBi2Ti2NbO10−δ would open new avenues in the design and discovery of other novel oxide-ion conductors. Parts of this paper have been published in the following journal articles. Zhang, W., Fujii, K., Niwa, E., Hagihala, M., Kamiyama, T., & Yashima, M. (2020). Oxide-ion conduction in the Dion–Jacobson phase CsBi2Ti2NbO10−δ.Nature communications, 11(1), 1–8.
Wenrui Zhang
Chapter 3. New Oxide-Ion Conductors of Dion–Jacobson-Type Layered Perovskites CsLn2Ti2NbO10 (Ln = La, Pr, Nd, Sm, Gd, Ho, and Yb) and CsLa2–xMxTi2+yNb1–yO10–x/2–y/2 (M = Ca, Sr, and Ba; x = 0, 0.1; y = 0.1, 0, and –0.1)
Abstract
As introduced in the Chap. 2, Dion–Jacobson-type layered perovskites have attracted much attention because of their novel physical and chemical properties such as ferroelectricity, photocatalyst, magnetism, and electrical conduction. The research in the caption presents a series of Dion–Jacobson phases of oxide-ion conductors. Dion–Jacobson phase CsLa2Ti2NbO10−δ and its related compounds of CsLn2Ti2NbO10 (Ln = La, Pr, Nd, Sm, Gd, Ho, and Yb) and CsLa2–xMxTi2+yNb1–yO10–x/2–y/2 (M = Ca, Sr, and Ba; x = 0, 0.1; y = 0.1, 0, and –0.1) were synthesized and some of the compositions’ electrical conductivity and crystal structure were investigated from room temperature to high temperature. Unlike the CsBi2Ti2NbO10–δ discussed in the Chap. 2, Rietveld's analysis of high-temperature neutron and synchrotron X-ray diffraction data revealed no phase transition from room temperature to 800 °C in the mother phase of CsLa2Ti2NbO10−δ, exhibiting good practical realizations and applications. Bond-valence-based energy landscapes of a test oxide ion show two-dimensional oxide-ion diffusion along the edges of an octahedron in the perovskite layers. The larger-sized Cs in CsLa2Ti2NbO10–δ make the larger bottlenecks for oxide-ion migration, which leads to the lower activation energy for the oxide-ion conduction. The present finding of oxide-ion conductivities in the Dion–Jacobson phase CsLa2Ti2NbO10–δ indicates that the wide possibility of Dion–Jacobson phase as oxide-ion conductors would open up new horizons in the discovery of other novel oxide-ion conductors, which based on the reported Dion–Jacobson phases.
Parts of this paper have been published in the following journal articles.
Zhang, W., Fujii, K., Ishiyama, T., Kandabashi, H., & Yashima, M. (2020). Dion–Jacobson-type oxide-ion conductor CsLa 2 Ti 2 NbO 10 − δ without phase transitions. Journal of Materials Chemistry A8(47), 25,085–25,093.
Wenrui Zhang
Chapter 4. Conclusion and Future Work
Abstract
Oxide-ion conductors exhibit many applications in various electrochemical devices such as solid-oxide fuel cells, gas sensors, and separation membranes. And the oxide-ion conductivity of a material is strongly dependent on its crystal structure. Therefore, it is important to discover new structural families of oxide-ion conductors.
Wenrui Zhang
Metadata
Title
Oxide-Ion Conduction in the Dion–Jacobson-Type Layered Perovskites
Author
Dr. Wenrui Zhang
Copyright Year
2022
Publisher
Springer Nature Singapore
Electronic ISBN
978-981-19-2247-3
Print ISBN
978-981-19-2246-6
DOI
https://doi.org/10.1007/978-981-19-2247-3