Fabrication of a room-temperature NO2 gas sensor using morphology controlled CVD-grown tellurium nanostructures

Abstract

A room-temperature (∼26 °C) NO2 gas sensor was fabricated using tellurium (Te) nanostructures. Te forms a helical chain with strong covalent bonds in the c-axis and weak van der Waals bonds between the chains. Therefore, the energy required for gas adsorption and desorption is low, thus, giving it the advantage of operating at room temperature. Since the shape and size of the Te helical chains can be freely controlled by adjusting the growth parameters, the electrical reactivities of Te to a specific gas can be controlled. In this study, the reactivity of Te to NO2 gas was controlled by adjusting the number of Te nanotube walls and lengths. It was also verified that the gas detection performance was maintained even with increasing humidity.