[행사/세미나] [Seminar] Feb. 27(Mon.) Topotactic redox engineering toward new/functional materials
- 물리학과
- 조회수3216
- 2023-02-20
에피산화물연구실에서 Stanford University의 김우진 박사님을 초청하여 아래와 같이 세미나를 개최합니다.
학과 구성원 여러분의 많은 참여를 부탁 드립니다.
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○ Topic: Topotactic redox engineering toward new/functional materials
○ Speaker: 김 우 진 박사님 (Stanford University)
○ Date/time: 2023. 2. 27. (Mon.) 11:00 AM
○ Place: Natural Science 1, Room No.31355
○ Abstract: Due to their multiple oxidation states, transition metal oxides can be existing in various forms with different structure symmetries. By selectively introducing or removing oxygen from specific sites in a crystal lattice, it is possible to manipulate the material's electronic structure, leading to the emergence of quantum phenomena, such as colossal magnetoresistance and superconductivity [1,2]. Topotactic redox reactions allow for this reversible reduction and oxidation process to occur without altering the relative structure of the cations of the material. In this talk, I will discuss a quasi-two-dimensional material system that is stabilized through topotactic reduction, where the Jahn-Teller effect results in a beautiful pattern of distortions. In the second half of the talk, I will introduce the use of mechanochemistry on freestanding oxide membranes to greatly reduce activation energy for redox reactions, which can be useful for creating new and clean functional oxides.
[1] R. von Helmolt et al., Phys. Rev. Lett. 71, 2331–2333 (1993).
[2] D. Li et al., Nature 572, 624–627 (2019).
*Supported by Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under contract No. DE-AC02-76SF00515.