Ultra-narrow WS₂nanoribbons encapsulated in carbon nanotubes

Layered tungsten disulfide nanostructures are of both fundamental and technological interest. The widths of currently synthesized WS2 ribbons are in the microscale. By using single-walled carbon nanotubes and double-walled carbon nanotubes as templates, we fabricate WS2 nanoribbons with smooth zigzag edges and uniform widths down to 1–3 nm and layer numbers down to 1–3, dependent on the nanotube diameter. Although bulk WS2 is a nonmagnetic...