Fabrication and characterization of ultrathin Ta₂(Pd or Pt)₃Se₈ nanowires

Miniaturization of semiconductor devices has been a prime focus of the electronics industry to address the requirements of next-generation electronic devices. One possible solution to tackle this problem is semiconducting one-dimensional (1D) van der Waals(vdW) wires. Here we present quasi 1D semiconducting Ta₂(Pd or Pt)₃Se₈(TPS) crystals, composed of weakly bound molecular ribbons. Inter-ribbon bonding energy(0.34eV/atom) of TPS bulk is 17 times weaker than the intra ribbon bonding energy(5.7eV/atom). In this work, we used cost-effective and easily processable liquid phase exfoliation technique to achieve molecularly thin wires. The thinnest nanowire we have readily achieved is around 1 nm, corresponding to a bundle of one or two molecular ribbons. Optimum solvent for the dispersion is investigated and found Di-acetone alcohol gives strong dispersion. High-resolution TEM, SEM and AFM studies were done to investigate the morphology and crystallinity of the ultrathin wires obtained. Our electrical transport measurements have shown that these thin wires are gatable and preserve the intrinsic bulk characteristics. The fabricated 1D transistors exhibit high switching performance and excellent ambient environment stability.