Single $\text{WS}_{2}$ Nanotube-Based Field Effect Transistor: Ambipolar Conduction and Self-Powered Photodetection

Semiconductive nanotubes offer the potential for miniaturized transistors with enhanced gate control through various configurations. In this work, we fabricated and electrically characterized a single $\text{W S}_{\text{2}}$ nanotube-based field-effect transistor under both dark and white light illumination at ambient pressure and temperature. At drain voltages higher than 1 V, the device exhibits ambipolar conduction, with a hole mobility of $0.2 ~\text{cm}^{2} ~\mathrm{V}^{-1} ~\mathrm{s}^{-1}$ and an electron mobility of $0.13 ~\text{cm}^{2} \mathrm{V}^{-1} ~\mathrm{s}^{-1}$ at $\mathrm{V}_{\text{ds}}=2 ~\mathrm{V}$. The gate modulation has been extensively investigated, applying gate voltages up to 100 V. Furthermore, the $\text{W S}_{\text{2}}$ nanotube-based device was evaluated as a photodetector, demonstrating light-induced modulation of the channel current via both gate and drain control. The single $\text{W S}_{\text{2}}$ nanotube-based transistor also operates in self-powered mode, achieving a short-circuit current of $\text{2. 6 ~ p A}$ and an open-circuit voltage of approximately 3 mV. The electrical properties of this device show potential for complementary metal-oxide semiconductor (CMOS) applications, and contribute to the development of optoelectronic devices, including self-powered photodetectors.