Reversible oxygen intercalation in hexagonal Y0.7Tb0.3MnO3+δ: toward oxygen production by temperature-swing absorption in air
Reversible oxygen intercalation in hexagonal Y0.7Tb0.3MnO3+δ: toward oxygen production by temperature-swing absorption in air
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DOI：
10.1039/c8ta09235d
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发表时间：
2019-02-14
影响因子：
11.9
通讯作者：
Takasaki, Akito
中科院分区：
文献类型：
--
作者：
Klimkowicz, Alicja;Cichy, Kacper;Takasaki, Akito
研究了六方相Y0.7Tb0.3MnO_3+在氧气和空气中的储氧容量、结构和热力学稳定性，以评价其变温吸附分离空气中氧的适用性。结果表明，在一定的氧分压下，用溶胶-凝胶法制备的Y0.7Tb0.3MnO_3~(3+)的小颗粒样品中可以可逆地掺入和提取大量的过量氧。在氧气或高压氧气氛中制备的β=0.45的超化学计量比材料具有新的六方结构，由中子衍射确定，在名义上五配位的Mn位附近有间隙氧缺陷，并得到扫描和透射电子显微镜的支持。热重测量表明，氧在300摄氏度左右的纯氧气气氛中可逆嵌入，但更重要的是，在空气中也是如此，温度范围非常窄，类似于20摄氏度，尽管产生的氧量较少
The oxygen storage capacity, structure and thermodynamic stability were studied for hexagonal Y0.7Tb0.3MnO3+delta in oxygen and air to assess its applicability for oxygen separation from air by a temperature-swing adsorption process. We show that large amounts of oxygen excess can be reversibly incorporated into and extracted from small particle-size samples of Y0.7Tb0.3MnO3+delta prepared by sol-gel synthesis for fixed oxygen partial pressures. The hyperstoichiometric material, with delta >= 0.45 prepared in oxygen or high-pressure oxygen atmospheres, assumes a new hexagonal structure with interstitial oxygen defects near the nominally five coordinated Mn site as determined by neutron diffraction and supported by scanning and transmission electron microscopy. Thermogravimetric measurements demonstrate reversible intercalation of oxygen in a pure O-2 atmosphere at around 300 degrees C, but more importantly, also in air over a remarkably narrow temperature range of similar to 20 degrees C, albeit producing smaller oxygen amounts delta