More and more attractive applications of two-dimensional (2D) materials in nanoelectronic devices are being achieved successfully, which promotes the rapid and extensive development of new 2D materials. In this work, the structural and electronic properties of the V structure aluminum phosphide (V-AlP) monolayer are examined by density functional calculations, and its electronic properties under strain and an electric field are also explored in detail. The computation results indicate that it has good stability. Interestingly, it possesses a wide direct gap (2.6 eV), and its band gap exhibits a rich behavior depending on the strain, E-field and layer stacking. Under biaxial strain, its band gap can be tuned from 1 eV to 2.6 eV. And a direct-indirect band gap transition is found when external tension is applied. The V-AlP monolayer also exhibits anisotropic behavior as its band structure variation trends under strains along different directions are obviously different. When the external E-field is changed from 0.5 V Å−1 to 1 V Å−1, the band gap of the V-AlP monolayer can be tuned linearly from 0 eV to 2.6 eV. Layer stacking narrows the band gap of the 2D V-AlP material. It is concluded that strain, E-field and layer stacking can all be used effectively to modify the electronic property of the V-AlP monolayer. Thus, these results indicate that the V-AlP monolayer will have promising applications in nanoelectric devices.
A new structure of monolayer h-CSe was predicted, exhibiting excellent stability. It was found to be an indirect semiconductor with a tunable bandgap by altering the strain and layer number. It also exhibits strong light harvesting ability.
The electronic and optical properties of three types of aluminum phosphide bilayers are examined using density functional theory. The results indicate that they all possess proper direct gaps, which exhibit a rich variety of behaviors depending on the strain. The band gaps of these aluminum phosphide bilayers could be easily tuned in the energy range from 0 eV to 1.9 eV under a wide range of biaxial strain. Additionally, band gap transitions between direct and indirect types are found when the external strain applied on them is changed from −12% to 12%. In addition, it was found that these AlP bilayers show strong light-harvesting ability for the ultraviolet light range of the solar spectrum (400–100 nm). The results obtained here indicate that these aluminum phosphide bilayers may have significant potential applications in future nanoelectric fields.
1 February 2019 in Journal of the European Ceramic Society