TY  - JOUR
AU  - Cao, Lei
AU  - Petracic, Oleg
AU  - Wei, Xian-Kui
AU  - Zhang, Hengbo
AU  - Duchoň, Tomáš
AU  - Gunkel, Felix
AU  - Koutsioumpas, Alexandros
AU  - Zhernenkov, Kirill
AU  - Rushchanskii, Konstantin Z.
AU  - Hartmann, Heinrich
AU  - Wilhelm, Marek
AU  - Li, Zichao
AU  - Xie, Yufang
AU  - He, Suqin
AU  - Weber, Moritz L.
AU  - Veltruská, Kateřina
AU  - Stellhorn, Annika
AU  - Mayer, Joachim
AU  - Zhou, Shengqiang
AU  - Brückel, Thomas
TI  - Migration Kinetics of Surface Ions in Oxygen‐Deficient Perovskite During Topotactic Transitions
JO  - Small
VL  - 17
IS  - 51
SN  - 1613-6810
CY  - Weinheim
PB  - Wiley-VCH
M1  - FZJ-2021-04437
SP  - 2104356
PY  - 2021
AB  - Oxygen diffusivity and surface exchange kinetics underpin the ionic, electronic, and catalytic functionalities of complex multivalent oxides. Towards understanding and controlling the kinetics of oxygen transport in emerging technologies, it is highly desirable to reveal the underlying lattice dynamics and ionic activities related to oxygen variation. In this study, the evolution of oxygen content is identified in real-time during the progress of a topotactic phase transition in La0.7Sr0.3MnO3-δ epitaxial thin films, both at the surface and throughout the bulk. Using polarized neutron reflectometry, a quantitative depth profile of the oxygen content gradient is achieved, which, alongside atomic-resolution scanning transmission electron microscopy, uniquely reveals the formation of a novel structural phase near the surface. Surface-sensitive X-ray spectroscopies further confirm a significant change of the electronic structure accompanying the transition. The anisotropic features of this novel phase enable a distinct oxygen diffusion pathway in contrast to conventional observation of oxygen motion at moderate temperatures. The results provide insights furthering the design of solid oxygen ion conductors within the framework of topotactic phase transitions.
LB  - PUB:(DE-HGF)16
C6  - 34791798
UR  - <Go to ISI:>//WOS:000719613100001
DO  - DOI:10.1002/smll.202104356
UR  - https://juser.fz-juelich.de/record/902642
ER  -