Comparative Studies for the Fabrication of WTe2 Nanoribbons in the Tellurization Process.

Tungsten ditelluride is a layered semimetal with higher-order topological insulator properties and robust one-dimensional (1D) states along certain crystallographic axes, making it promising for future spintronic applications. While bulk and exfoliated materials have been extensively studied, WTe2 nanoribbons and nanowires offer advantages for probing edge-state physics due to their enhanced surface-to-volume ratio and confined geometry. However, existing growth approaches for producing WTe2 nanostructures struggle to yield materials of sufficient quality. In this work, we investigate the growth and charge transport characteristics of WTe2 nanoribbons (NRs) synthesized through the tellurization of WO3 nanoribbons, comparing how different precursor compositions, WO3 with and without a NaCl:Te additive, alter the resulting material properties. The tellurization of the ribbons obtained using a NaCl:Te additive allows the production of highly crystalline WTe2. Charge transport measurements for individual WTe2 nanoribbon four-terminal devices indicate that surface capping is essential to prevent rapid oxidation. This study establishes a pathway for the fabrication of freestanding WTe2 nanoribbons of different geometrical parameters via the tellurization process.