TaS₃ Nanofibers: Layered Trichalcogenide for High-Performance Electronic and Sensing Devices

Layered materials, like transition metal dichalcogenides, exhibit broad spectra with outstanding properties with huge application potential, whereas another group of related materials, layered transition metal trichalcogenides, remains unexplored. Here, we show the broad application potential of this interesting structural type of layered tantalum trisulfide prepared in a form of nanofibers. This material shows tailorable attractive electronic properties dependent on the tensile strain applied to it. Structure of this so-called orthorhombic phase of TaS₃ grown in a form of long nanofibers has been solved and refined. Taking advantage of these capabilities, we demonstrate a highly specific impedimetric NO gas sensor based on TaS₃ nanofibers as well as construction of photodetectors with excellent responsivity and field-effect transistors. Various flexible substrates were used for the construction of a NO gas sensor. Such a device exhibits a low limit of detection of 0.48 ppb, well under the allowed value set by environmental agencies for NO_x (50 ppb). Moreover, this NO gas sensor also showed excellent selectivity in the presence of common interferences formed during fuel combustion. TaS₃ nanofibers produced in large scale exhibited excellent broad application potential for various types of devices covering nanoelectronic, optoelectronic, and gas-sensing applications.