二次元材料の新しい世界が開かれつつある(A new world of 2D material is opening up)

2024-03-15 リンショーピング大学

In a film that measures only a single millimetre, there can be millions of layers of 2D materials which generates its unique properties.　Foto:Olov Planthaber

＜関連情報＞

• https://liu.se/en/news-item/ny-varld-av-2d-material-oppnas
• https://www.science.org/doi/10.1126/science.adj6556

大規模計算と化学的剥離による層状固体の二次元材料 Two-dimensional materials by large-scale computations and chemical exfoliation of layered solids

JONAS BJÖRK, JIE ZHOU, PER O. Å. PERSSON, AND JOHANNA ROSEN
Science  Published:14 Mar 2024
DOI:https://doi.org/10.1126/science.adj6556

Editor’s summary

MXenes are a family of layered inorganic compounds made of transition metal carbides, nitrides, or carbonitrides. They are most often obtained through the selective etching of three-dimensional (3D) parent materials under acidic conditions. One open question is whether there are other layered materials that might be obtained using existing chemical processes. Björk et al. describe a method for high-throughput screening using computation to determine which 3D materials might undergo successful chemical exfoliation (see the Perspective by Thakur and Anasori). The authors identified 119 possible candidates, from which they experimentally synthesized Ru₂Si_xO_y nanosheets from a parent YRu₂Si₂ compound, a material quite different from the standard families of MXenes. —Marc S. Lavine

Abstract

MXenes are a family of two-dimensional (2D) materials typically formed by etching the A element from a parent MAX phase. Computational screening for other 3D precursors suitable for such exfoliation is challenging because of the intricate chemical processes involved. We present a theoretical approach for predicting 2D materials formed through chemical exfoliation under acidic conditions by identifying 3D materials amenable for selective etching. From a dataset of 66,643 3D materials, we identified 119 potentially exfoliable candidates, within several materials families. To corroborate the method, we chose a material distinctly different from MAX phases, in terms of structure and chemical composition, for experimental verification. We selectively etched Y from YRu₂Si₂, resulting in 2D Ru₂Si_xO_y. The high-throughput methodology suggests a vast chemical space of 2D materials from chemical exfoliation.