Modulations of the Work Function and Morphology of a Single MoS2 Nanotube by Charge Injection

A current was injected into a single MoS2 nanotube using an atomic-force-microscopy probe. The trapped electrons and holes caused a partial collapse of the nanotube and its helical twisting. The topography changes can be explained by the reverse piezoelectric effect, the theory of which was proposed for chiral nanostructures. Work-function modifications were observed, which were dependent on the polarity of the injected carriers.