Nitrogen and beryllium pressed into service as new 2D material

An international team, including researchers from the University of Bayreuth in Germany, has succeeded in discovering a previously unknown two-dimensional (2D) material using modern high-pressure technology.

The new material, beryllonitrene, consists of regularly arranged nitrogen and beryllium atoms, and possesses an unusual electronic lattice structure that shows great potential for applications in quantum technology. Its synthesis required a compression pressure about one million times higher than the pressure of the Earth's atmosphere. The researchers report their discovery in a paper in Physical Review Letters.

Since the discovery of graphene, comprising a single-atom-thick layer of carbon atoms, interest in so-called 2D materials has grown steadily in research and industry. Under extremely high pressures of up to 100 gigapascals, researchers from the University of Bayreuth, together with international partners, managed to produce compounds composed of nitrogen and beryllium atoms. Known as beryllium polynitrides, these compounds vary in their crystal structure: some conform to the monoclinic crystal system, while others conform to the triclinic crystal system.

The triclinic beryllium polynitrides exhibit one unusual characteristic when the pressure drops: they take on a crystal structure made up of layers. Each layer contains zigzag nitrogen chains connected by beryllium atoms, which can be described as a planar structure consisting of BeN₄ pentagons and Be₂N₄ hexagons. This means each individual layer represents a 2D material, which the researchers termed beryllonitrene.

Qualitatively, beryllonitrene is a new 2D material. Unlike graphene, the 2D crystal structure of beryllonitrene results in a slightly distorted electronic lattice. Because of its electronic properties, beryllonitrene should be particularly suited for applications in quantum technology, if it could one day be produced on an industrial scale. In this still young field, the aim is to use the quantum mechanical properties and structures of materials for technical innovations – for example, constructing high-performance computers or developing novel encryption techniques for secure communication.

"For the first time, close international cooperation in high-pressure research has now succeeded in producing a chemical compound that was previously completely unknown," says co-author Natalia Dubrovinskaia from the Laboratory for Crystallography at the University of Bayreuth. "This compound could serve as a precursor for a 2D material with unique electronic properties. The fascinating achievement was only possible with the help of a laboratory-generated compression pressure almost a million times greater than the pressure of the Earth's atmosphere. Our study thus once again proves the extraordinary potential of high-pressure research in materials science."

"However, there is no possibility of devising a process for the production of beryllonitrene on an industrial scale as long as extremely high pressures, such as can only be generated in the research laboratory, are required for this," adds corresponding author Leonid Dubrovinsky from the Bavarian Research Institute of Experimental Geochemistry & Geophysics at the University of Bayreuth. "Nevertheless, it is highly significant that the new compound was created during decompression and that it can exist under ambient conditions. In principle, we cannot rule out that one day it will be possible to reproduce beryllonitrene or a similar 2D material with technically less complex processes and use it industrially. With our study, we have opened up new prospects for high-pressure research in the development of technologically promising 2D materials that may surpass graphene."

This story is adapted from material from the University of Bayreuth, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.