Ta₂Ni₃Se₈: 1D van der Waals Material with Ambipolar Behavior

In this study, high-purity and centimeter-scale bulk Ta₂Ni₃Se₈ crystals are obtained by controlling the growth temperature and stoichiometric ratio between tantalum, nickel, and selenium. It is demonstrated that the bulk Ta₂Ni₃Se₈ crystals could be effectively exfoliated into a few chain-scale nanowires through simple mechanical exfoliation and liquid-phase exfoliation. Also, the calculation of electronic band structures confirms that Ta₂Ni₃Se₈ is a semiconducting material with a small bandgap. A field-effect transistor is successfully fabricated on the mechanically exfoliated Ta₂Ni₃Se₈ nanowires. Transport measurements at room temperature reveal that Ta₂Ni₃Se₈ nanowires exhibit ambipolar semiconducting behavior with maximum mobilities of 20.3 and 3.52 cm² V⁻¹ s⁻¹ for electrons and holes, respectively. The temperature-dependent transport measurement (from 90 to 295 K) confirms the carrier transport mechanism of Ta₂Ni₃Se₈ nanowires. Based on these characteristics, the obtained 1D vdW material is expected to be a potential candidate for additional 1D materials as channel materials.