Barium Indate-Zirconate Perovskite Oxyhydride with Enhanced Hydride Ion/Electron Mixed Conductivity
Barium Indate-Zirconate Perovskite Oxyhydride with Enhanced Hydride Ion/Electron Mixed Conductivity
复制标题
具有增强氢化物离子/电子混合电导率的锆酸钡钙钛矿氢氧化物
DOI：
10.1021/acs.chemmater.2c01467
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发表时间：
2022
影响因子：
8.6
通讯作者：
and Y. Aoki
中科院分区：
文献类型：
--
作者：
H. Toriumi;G. Kobayashi;T. Saito;T. Kamiyama;T. Sakai;T. Nomura;S. Kitano;H. Habazaki;and Y. Aoki
由于氢化物（H-）离子的导电性和氧化还原活性的协同效应，氢氧化物作为电化学和催化材料具有优异的潜力。然而，苛刻的制备条件及其热解性质限制了它们的应用。在此，我们发现了高度耐用的氢氧钙钛矿BaZr0.5In(II)0.5O2.25H0.5，具有增强的H-离子-电子混合电导率。 BaZr0.5In(III)0.5O2.75 作为母相，通过简单的 H2 气体退火在 800 °C 环境压力下还原氢化为 BaZr0.5In(II)0.5O2.25H0.5，并结合 H 离子，同时形成氧空位。通过传统的烧结和后还原制造了多孔镍金属陶瓷载体上包含致密 BaZr0.5In0.5O2.25H0.5 薄膜的膜装置，因为氢化后的低晶格收缩（-0.07％）允许 BaZr0.5In0.5O2.75 烧结体的整体氢化而不会导致结构崩溃。由此产生的器件在 500 °C 下表现出比质子陶瓷器件更高的氢渗透性，因为 BaZr0.5In(II)0.5O2.25H0.5 由于显着高的氧缺陷（25% 的 O 位点是空的），允许 H 离子在最邻近的阴离子位点之间跳跃，从而产生 10-3S cm-1 的 H 离子电导率。鉴于其优异的氢离子电导率和易于制造，该合成材料在陶瓷电化学电池的混合导电电极和透氢膜支架方面具有巨大的应用潜力。
Oxyhydrides have excellent potential as electrochemical and catalytic materials owing to the synergistic effects of the conductivity and redox activity of the hydride (H–) ion. However, harsh preparation conditions and their pyrolytic nature limit their applications. Herein, we discover highly durable oxyhydride perovskite BaZr0.5In(II)0.5O2.25H0.5with enhanced H–ion–electron mixed conductivity. BaZr0.5In(III)0.5O2.75, as the parent phase, was reductively hydrogenated to BaZr0.5In(II)0.5O2.25H0.5via simple H2gas annealing at 800 °C under an ambient pressure with the incorporation of H–ions with simultaneous oxygen vacancy formation. Membrane devices comprising dense BaZr0.5In0.5O2.25H0.5films on porous Ni-cermet supports were fabricated by conventional sintering and postreduction because low lattice contraction (−0.07%) following hydrogenation allowed for the bulk hydrogenation of BaZr0.5In0.5O2.75sinters without structural collapse. The resulting devices exhibited higher hydrogen permeability than protonic ceramic ones at 500 °C because BaZr0.5In(II)0.5O2.25H0.5allows H–ion hopping between the nearest-neighbor anion sites due to the significantly high oxygen deficiency (25% of O sites are vacant), giving rise to a H–ion conductivity of 10–3S cm–1. Given their superior H–ion conductivity and ease of manufacturing, the synthesized materials have great potential for applications in mixed conducting electrodes and hydrogen-permeable membrane supports of ceramic electrochemical cells.