Structural, electronic, and transport properties of 1D Ta₂Ni₃Se₈ semiconducting material

Due to their unique properties and potential applications, van der Waals (vdW) crystals with covalently bonded building blocks through vdW interactions have sparked widespread interest. In this article, we introduce a Ta₂Ni₃Se₈ material as an example of an emerging one-dimensional (1D)-vdW-based material. Recently, it was demonstrated that bulk Ta₂Ni₃Se₈ crystals may be effectively exfoliated into a few-chain-scale nanowires using simple mechanical and liquid-phase exfoliation. We performed density-functional theory calculations to get a better understanding of its electrical, magnetic, and transport properties. Theoretically, we expect that this Ta₂Ni₃Se₈ is a semiconducting material, displaying the indirect-to-direct bandgap transition from bulk to single, as well as the band splitting and bandgap opening with the inclusion of Coulomb interaction. Based on deformation potential theory, the carrier mobility of bulk Ta₂Ni₃Se₈ along the axis direction (a-axis) is as high as 264.00 cm² V⁻¹ s⁻¹ for electrons and 119.62 cm² V⁻¹ s⁻¹ for holes. The calculated carrier mobility of Ta₂Ni₃Se₈, a 1D single nanowire, is 59.60 cm² V⁻¹ s⁻¹ for electrons and 42.90 cm² V⁻¹ s⁻¹ for holes, which is comparable to that of other 1D materials. This confirms that a recently developed field-effect transistor based on Ta₂Ni₃Se₈ nanowires exhibits maximum experimental mobilities of 20.3 and 3.52 cm² V⁻¹ s⁻¹ for electrons and holes, respectively. On the basis of the obtained intriguing properties of 1D vdW Ta₂Ni₃Se₈ material, it is expected to be a potential candidate for additional 1D materials as channel materials.