Ran Ke, Zeng Fanlin, Jin Lei, Baumann Stefan, Meulenberg Wilhelm A, Mayer Joachim
Central Facility for Electron Microscopy GFE, RWTH Aachen University, Aachen, Germany.
Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons ER-C, Forschungszentrum Jülich GmbH, Jülich, Germany.
Nat Commun. 2024 Sep 17;15(1):8156. doi: 10.1038/s41467-024-52386-3.
Ceria-based oxides are widely utilized in diverse energy-related applications, with attractive functionalities arising from a defective structure due to the formation of mobile oxygen vacancies ( ). Notwithstanding its significance, behaviors of the defective structure and in response to external stimuli remain incompletely explored. Taking the Gd-doped ceria (CeGdO) as a model system and leveraging state-of-the-art transmission electron microscopy techniques, reversible phase transitions associated with massive rearrangement are stimulated and visualized in situ with sub-Å resolution. Electron dose rate is identified as a pivotal factor in modulating the phase transition, and both the concentration and the orientation of the newly formed phase can be altered via electron beam. Our results provide indispensable insights for understanding and refining the microscopic pathways of phase transition as well as defect engineering, and could be applied to other similar functional oxides.
基于二氧化铈的氧化物被广泛应用于各种与能源相关的领域，由于形成了可移动的氧空位（ ），其缺陷结构产生了吸引人的功能。尽管其具有重要意义，但缺陷结构及其对外部刺激的响应行为仍未得到充分探索。以钆掺杂二氧化铈（CeGdO）为模型系统，并利用最先进的透射电子显微镜技术，与大量 重排相关的可逆相变被激发，并以亚埃分辨率进行原位可视化。电子剂量率被确定为调节相变的关键因素，新形成相的 浓度和取向都可以通过电子束改变。我们的结果为理解和完善相变的微观途径以及缺陷工程提供了不可或缺的见解，并可应用于其他类似的功能氧化物。
