A Metastable Pentagonal 2D Material Synthesized by Symmetry-Driven Epitaxy

Lina Liu; Yujin Ji; Marco Bianchi; Saban M. Hus; Zheshen Li; Richard Balog; Jill A. Miwa; Philip Hofmann; An-ping Li; Dmitry Y. Zemlyanov; Youyong Li; Yong P. Chen

arXiv · 2408.04095

A Metastable Pentagonal 2D Material Synthesized by Symmetry-Driven Epitaxy

Lina Liu·Yujin Ji·Marco Bianchi·Saban M. Hus·Zheshen Li·Richard Balog·Jill A. Miwa·Philip Hofmann·An-ping Li·Dmitry Y. Zemlyanov·Youyong Li·Yong P. Chen

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Abstract

Most two-dimensional (2D) materials experimentally studied so far have hexagons as their building blocks. Only a few exceptions, such as PdSe2, are lower in energy in pentagonal phases and exhibit pentagons as building blocks. While theory has predicted a large number of pentagonal 2D materials, many of them are metastable and their experimental realization is difficult. Here we report the successful synthesis of a metastable pentagonal 2D material, the monolayer pentagonal PdTe2, by symmetry-driven epitaxy. Scanning tunneling microscopy and complementary spectroscopy measurements are used to characterize the monolayer pentagonal PdTe2, which demonstrates well-ordered low-symmetry atomic arrangements and is stabilized by lattice matching with the underlying Pd(100) substrate. Theoretical calculations, along with angle-resolved photoemission spectroscopy, reveal monolayer pentagonal PdTe2 is a semiconductor with an indirect bandgap of 1.05 eV. Our work opens an avenue for the synthesis of pentagon-based 2D materials and gives opportunities to explore their applications such as multifunctional nanoelectronics.

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Lina Liu, Yujin Ji, Marco Bianchi, Saban M. Hus, Zheshen Li, Richard Balog, Jill A. Miwa, Philip Hofmann, An-ping Li, Dmitry Y. Zemlyanov, Youyong Li, Yong P. Chen. 2024-08-07. A Metastable Pentagonal 2D Material Synthesized by Symmetry-Driven Epitaxy. https://arxiv.org/abs/2408.04095

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