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

doi:10.1038/s41563-024-01987-w

A metastable pentagonal 2D material synthesized by symmetry-driven epitaxy

Nat Mater. 2024 Oct;23(10):1339-1346. doi: 10.1038/s41563-024-01987-w. Epub 2024 Aug 27.

Authors

Lina Liu^#^{1

2

3}, Yujin Ji^#⁴, Marco Bianchi⁵, Saban M Hus⁶, Zheshen Li⁷, Richard Balog³, Jill A Miwa⁵, Philip Hofmann⁵, An-Ping Li⁶, Dmitry Y Zemlyanov⁸, Youyong Li⁹, Yong P Chen^{10

11

12

13}

Affiliations

¹ Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA.
² Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA.
³ Department of Physics and Astronomy and Villum Center for Hybrid Quantum Materials and Devices, Aarhus University, Aarhus, Denmark.
⁴ Institute of Functional Nano and Soft Materials, Soochow University, Suzhou, China.
⁵ Department of Physics and Astronomy and Villum Center for Dirac Materials, Aarhus University, Aarhus, Denmark.
⁶ Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA.
⁷ Department of Physics and Astronomy and Center for Storage Ring Facilities (ISA), Aarhus University, Aarhus, Denmark.
⁸ Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA. dzemlian@purdue.edu.
⁹ Institute of Functional Nano and Soft Materials, Soochow University, Suzhou, China. yyli@suda.edu.cn.
¹⁰ Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA. yongchen@purdue.edu.
¹¹ Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA. yongchen@purdue.edu.
¹² Department of Physics and Astronomy and Villum Center for Hybrid Quantum Materials and Devices, Aarhus University, Aarhus, Denmark. yongchen@purdue.edu.
¹³ Purdue Quantum Science and Engineering Institute and School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, USA. yongchen@purdue.edu.

^# Contributed equally.

PMID: 39191980
DOI: 10.1038/s41563-024-01987-w

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. Although theory has predicted a large number of pentagonal 2D materials, many of these are metastable and their experimental realization is difficult. Here we report the successful synthesis of a metastable pentagonal 2D material, monolayer pentagonal PdTe₂, by symmetry-driven epitaxy. Scanning tunnelling microscopy and complementary spectroscopy measurements are used to characterize this material, 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 to be 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.

Abstract

Grants and funding