Ta 2 Ni 3 Se 8 : 1D van der Waals Material with Ambipolar Behavior.

In this study, high-purity and centimeter-scale bulk Ta ₂ Ni ₃ Se ₈ crystals are obtained by controlling the growth temperature and stoichiometric ratio between tantalum, nickel, and selenium. It is demonstrated that the bulk Ta ₂ Ni ₃ Se ₈ 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 Ta ₂ Ni ₃ Se ₈ is a semiconducting material with a small bandgap. A field-effect transistor is successfully fabricated on the mechanically exfoliated Ta ₂ Ni ₃ Se ₈ nanowires. Transport measurements at room temperature reveal that Ta ₂ Ni ₃ Se ₈ nanowires exhibit ambipolar semiconducting behavior with maximum mobilities of 20.3 and 3.52 cm ² 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 Ta ₂ Ni ₃ Se ₈ nanowires. Based on these characteristics, the obtained 1D vdW material is expected to be a potential candidate for additional 1D materials as channel materials.
(© 2021 Wiley-VCH GmbH.)