摘要
钙钛矿型过渡金属氧化物SrCrO_3随着温度和压力等条件的变化会呈现出相变和物理性质的变化,因而引起了科学家们的广泛关注。本文通过扫描透射电子显微学和电子能量损失谱等表征方法,研究了电子束辐照条件下SrCrO_3结构的演化行为。结果表明,电子束辐照可以诱导SrCrO_3产生新的调制结构相,且这种调制结构是由电子束辐照产生的有序氧空位所形成的。本文构建了空间群为I4/mmm的调制结构SrCrO_(2.5),并通过第一性原理计算对该结构模型进行了优化。基于该结构模拟的SAED和STEM图像与实验结果吻合得较好。
The perovskite-type transition metal oxide SrCrO3,displaying structural transitions and novel physical properties with temperature and pressure,has gained extensive attention. In this paper,the structural transition of single crystal SrCrO3 under electron beam irradiation（ EBI） is investigated by means of scanning transmission electron microscopy（ STEM） and electron energy-loss spectroscopy（ EELS）. The results show that the electron beam irradiation induces a new modulation structure from the pristine structure of SrCrO3. The EELS spectra illustrate that the modulation structure is formed by ordered oxygen vacancies generated by EBI.A possible crystal structure of the modulation structure SrCrO（2. 5）（ I4/mmm） is constructed and optimized by the first principles calculations. The simulated SAED patterns and STEM images match well with the experimental ones.
作者
许明慧
曹立朋
王伟鹏
丁一凡
沈希
姚湲
靳常青
禹日成
XU Ming-hui;CAO Li-peng;WANG Wei-peng;DING Yi-fan;SHEN Xi;YAO Yuan;JIN Chang-qing;YU Ri-cheng(Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190;School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 101407,China)
出处
《电子显微学报》
CAS
CSCD
北大核心
2018年第3期226-231,共6页
Journal of Chinese Electron Microscopy Society
基金
国家重点研发计划项目(Nos.2016YFA0300701,2017YFA0206200)
国家自然科学基金资助项目(Nos.11574376,11374343)
