Data from: Electrical properties of MoS2 nanotubes

The demand for ultra-low-power, high-performance computing devices continues to drive the advancement of electronic technologies. Among emerging materials, molybdenum disulfide (MoS2) has attracted significant attention due to its favorable electronic and quantum properties, particularly when transitioning from bulk to two-dimensional structures. While MoS2 monolayers have been extensively studied, the electrical behavior of MoS2 nanotubes remains largely unexplored.

In this work, MoS2 nanotubes in cylindrical and collapsed shapes synthesized via chemical vapor transport are investigated, revealing low defect densities and a continuous chiral interface. The surface morphology of collapsed nanotubes is found to be non-uniform and wrinkled, where elevated regions exhibit higher conductivity than depressed areas. In contrast, the highly curved edges display pronounced conductivity variations, ranging from insulating to highly conductive behavior, suggesting localized electron confinement.

Charge injections are shown to significantly modify the surface potential of the nanotubes. Due to the strong anisotropy between in-plane and out-of-plane conductivity in MoS2, injected charge carriers predominantly propagate laterally. However, this transport is influenced by structural imperfections such as defects, edge terminations, and interfacial strain. Additionally, overlapping nanotubes and surface flakes alter local electronic properties through mechanisms including charge trapping, electrostatic gating, and strain-induced scattering.

Furthermore, charge injections induce reversible geometrical changes in cylindrical and in collapsed nanotubes. These deformations, observed as helical twisting along the nanotube axis and gradual plastic deformation, are attributed to a rotational component of the inverse piezoelectric effect inherent to chiral structures. The magnitude of this response depends on factors such as nanotube diameter, chirality, and prior charge injection history.

Notably, the long-term persistence of these shape changes was observed, which can be attributed to the accumulation of structural defects and the associated strain, potentially enabling memory-like charge confinement.

The choice of substrate can shift the work function of MoS2 nanotubes by several hundred millivolts, directly influencing Schottky barrier heights, charge injection, and contact resistance - findings critical for contact engineering and device fabrication.

Overall, these findings highlight the importance of nanoscale structural and electrical characterization for understanding and engineering charge transport in MoS2 nanotubes. This insight is essential for the development of defect-tolerant, high-performance devices based on transition metal dichalcogenides.