First Experimental Realization of a 2D Pentagonal Material

First Experimental Realization of a 2D Pentagonal Material

Scientific Achievement
Crystallographic structure of puckered pentagonal palladium diselenide.  (hi-res image)

Layers of a pentagonally tiled 2D crystal (PdSe2) were experimentally isolated and electronically characterized, revealing high electron mobility and air-stability.

Significance and Impact

The anisotropic, puckered structure of the pentagonally tiled 2D PdSe2 crystal enables a variety of emerging physics and disruptive applications, from magnetic frustration to spintronics. 

Research Details

- Layers of a pentagonally tiled 2D crystal, PdSe2 , were experimentally isolated and characterized for the first time.
- Micro-absorption optical spectroscopy, Raman and first-principles calculations revealed a strong variation of the band gap with the number of layers, from 0.2eV (bulk) to 1.3eV (monolayer).
- Few-layer PdSe2 devices displayed tunable ambipolar transport behavior with high carrier mobility and surprising air stability.
A. Oyedele, S. Yang, L. Liangbo, A. A Puretzky, K. Wang, J. Zhang, P. Pudasaini, A. W. Ghosh, Z. Liu, C. Rouleau, B. G. Sumpter, M. F. Chisholm, W. Zhou, D. B. Geohegan, K. Xiao, "PdSe2: Pentagonal 2D Layers with High Air Stability for Electronics," J. Am. Chem. Soc. (2017), “Just Accepted” manuscript published on-line). DOI: 10.1021/jacs.7b04865

CNMS Researchers