Molybdenum mo powder

Growth of single crystals: Large, well-formed, ribbon-like single crystals of MoTe2 and Mo0.9W0.1Te2 alloy were grown by chemical vaper transport (CVT) with iodine (I) as the carrier gas. Stoichiometric amounts of tungsten (W) powder (99.9%, Sigma-Aldrich), molybdenum (Mo) powder (99.95%, Sigma-Aldrich) and tellurium (Te) powder (99.95%, Sigma-Aldrich) with a total weight of 500 mg, plus an extra 35 mg of I as the transport gas were sealed in an evacuated 20 cm long quartz tube under vacuum at 10 -6 Torr. The quartz tube was placed in a three-zone furnace. Firstly, the reaction zone was maintained at 850 °C for 30 h with the growth zone at 900 °C in order to prevent the transport of the product and a complete reaction; then the reaction zone was heated to 1070 °C and held for 7 days with the growth zone at 950 °C. Finally, the furnace was naturally cooled down to room temperature and the single crystals were collected in the growth zone. Residual I was cleaned using acetone before measurement.
Device fabrication: Devices were fabricated on exfoliated MoTe2 or Mo0.9W0.1Te2 flakes with thickness ranging from 100~300 nm and typical dimensions being 20 um ×20 um assembled on SiO2/Si substrates. Electrodes were defined by electron beam lithography followed by physical vapor deposition of 300 nm Ti/100 nm Au film.