Arsenén

Arsenén, also known as arsenene in English, is a two-dimensional allotrope of arsenic. Like phosphorene for phosphorus, arsenene refers to single-layer sheets of arsenic atoms arranged in low-dimensional lattices. The material has been the subject of theoretical work since the mid-2010s, with several structural variants proposed.

The principal structural forms are commonly described as alpha-arsenene, a puckered lattice similar to black phosphorus, and beta-arsenene, a buckled honeycomb configuration. These polymorphs exhibit anisotropic properties arising from their distinct bonding geometries. The electronic structure is predicted to be semiconducting, with a bandgap that depends on the precise structure, number of layers, and the interactions with substrates or encapsulation. The ability to tune the bandgap and carrier mobility through strain, stacking, or chemical modification is a recurring theme in theoretical studies.

Synthesis and stability present significant challenges. Arsenene is relatively reactive with air and oxygen, which complicates isolation and device integration. Early experimental reports have explored growth on suitable substrates or mechanical exfoliation from layered arsenic precursors, but achieving stable, large-area monolayers remains difficult. Encapsulation and inert-atmosphere handling are commonly employed in laboratory investigations.

Safety considerations are important: arsenic and its compounds are highly toxic, necessitating rigorous safety protocols, proper containment, and careful waste management in all handling and fabrication processes.

Research on arsenene is ongoing, with goals including validating predicted properties, understanding substrate and environmental effects, and exploring potential applications in nanoelectronics, optoelectronics, and energy storage. See also: arsenene, arsenic, phosphorene, two-dimensional materials.