Unconventional ribbon-shaped beta-Ga2O3 tubes with mobile Sn nanowire fillings

We report on the synthesis of novel, unconventional beta-Ga(2)O(3) tubes via a Sn nanowire template process using thermal decomposition and oxidation of SnO and GaN powder mixtures. Distinctly different from any previously reported nano- and microtubes, the present beta-Ga(2)O(3) tubes display a flattened and thin belt-like (or ribbon-like) morphology. Each ribbon-shaped tube has a width of approximately 1-2 microm over its entire length, a length in the range of tens of micrometers, a thickness of approximately 100-150 nm, and a uniform inner diameter of 30-120 nm. The tubes were either partially or completely filled with Sn nanowires, forming Sn/Ga(2)O(3) metal-semiconductor nanowire heterostructures. A convergent electron beam generated in a transmission electron microscope is demonstrated to be an effective tool for delicate manipulation of encapsulated Sn nanowires. The Sn nanowires were gently cut apart (into two discrete fragments) and then completely separated and rejoined within Ga(2)O(3) ribbon-shaped tubes. These unconventional beta-Ga(2)O(3) tubes not only should enrich the well-established bank of nanostructured morphologies and extend the understanding of crystal growth at the nanoscale but also may have promise for the design of electron-beam-irradiation- or thermo-driven electrical switches.