学生のCHIEW, Yi Lingさん (博士後期課程２年、応用物理学領域、大島研究室)が, シンガポールで開催された国際会議 10th International Conference on Materials for Advanced Technologies (ICMAT)（参加者約3,000人）において最優秀ポスター賞を受賞しました。
　本成果は小矢野研究室（環境・エネルギー領域）との共同研究によるものです。

■受賞年月日
　令和元年6月28日

■論文タイトル
Unravelling Planar Distribution of Intercalated Fe Atoms in TiS2 Layered Structure Using Transmission Electron Diffraction

■著者
　Y. CHIEW, S. ABE, M. MIYATA, M. KOYANO, Y. OSHIMA

■論文概要
The discovery of new functions by intercalating guest atoms into host layered materials have attracted attention due to the wide possibilities of applications achievable. These intercalated 2-dimensional materials are known to form complex superlattices, which are difficult to analyze. For example, the material in this study, FexTiS2, has been reported to form 2a×2a or √3a×√3a superlattices for x = 1/4 or 1/3, respectively (a is the lattice constant of the TiS2 layer) where the Fe atoms occupy octahedral sites. However, in our study, a new, larger superlattice is proposed for FexTiS2 (grown with nominal content x = 0.33), based on the transmission electron diffraction (TED) pattern. TED is a powerful method that can be used to clarify two-dimensional atomic structures such as the Si (111) 7×7 reconstruction. Using the Patterson map constructed from TED pattern, the superlattice is observed to have P3 symmetry with unit lengths of √43 a× √43 a, rotated at an angle of 7.5888°. Further analysis of the TED pattern and its Patterson map also allowed the determination of the planar distribution of Fe atoms. Nine Fe atoms are found to be present in the unit cell and the Fe atoms occupy not only octahedral sites, as reported previously, but in tetrahedral sites as well.

■受賞にあたっての一言
It is a great honor to receive this award from the conference. I am extremely grateful to Prof. Yoshifumi Oshima, Prof. Mikio Koyano and Assistant Prof. Masanobu Miyata for the constant guidance. I would also like to thank the staff of Nanotechnology Platform in JAIST for their support with my sample preparation and characterization. And last by not least, I would like to thank all my lab members and friends for always being there for me.

令和元年7月3日