Comunicazione
Multiwalled $WS_{2}$ nanotubes forest for visible-light photodetectors.
De Stefano S., Durante O., Capista D., Passacantando M., Zak A., Giubileo F., Camilli L., Di Bartolomeo A.
One-dimension semiconductors are currently receiving much attention due to their unique electronic and optoelectronic properties. In particular, Transition Metal Dichalcogenides (TMDs) materials have become very fascinating owing to their layer-tunable bandgap, in terms of amplitude and its nature (direct or indirect). This makes them very promising for application in high-sensitivity, and ultra-fast photodetectors and phototransistors. In this work, we estimate the semiconductor behavior of a thin film of randomly oriented multiwalled tungsten disulfide nanotubes ($WS_{2}$NTs) drop-casted on an interdigitated electrode architecture, focusing on temperature response. We study the photocurrent dependence on both wavelength and pressure ($i.e.$, amplitude and relaxation times), and the effective bandgap of $WS_{2}$NTs forest. This analysis reveals a bandgap value of 1.87 eV, an increase in photocurrent compared to the single $WS_{2}$NT one, and different photocurrent values in several pressure conditions. Therefore, $WS_{2}$NTs are suitable for photodetection applications under a wide range of conditions.