WS2 Nanotubes: Electrical Conduction and Field Emission Under Electron Irradiation and Mechanical Stress

This study reports the electrical transport and the field emission properties of individual multi-walled tungsten disulphide (WS2) nanotubes (NTs) under electron beam irradiation and mechanical stress. Electron beam irradiation is used to reduce the nanotube-electrode contact resistance by one-order of magnitude. The field emission capability of single WS2NTs is investigated, and a field emission current density as high as 600 kA cm(-2)is attained with a turn-on field of approximate to 100 V mu m(-1)and field-enhancement factor approximate to 50. Moreover, the electrical behavior of individual WS2NTs is studied under the application of longitudinal tensile stress. An exponential increase of the nanotube resistivity with tensile strain is demonstrated up to a recorded elongation of 12%, thereby making WS2NTs suitable for piezoresistive strain sensor applications.