Photoconductive Electrospun Titania Nanofibres to Develop Gas Sensors Operating at Room Temperature

The use of nanostructured materials, such as those based on metal or metal oxides, has opened a new way to enhance the performances of chemical sensors making them able to detect gases at ppb level. In this type of sensors, the conductance is modulated by the presence of analytes that interact through physical-chemical processes of absorption and desorption, inducing changes in mobility or carriers density. The nano-scale dimensions of these materials enhance the interaction phenomena in terms of time and responses. In order to activate the physical/chemical interaction processes of the sensors based on oxide materials, an high operating temperature (200-400 degrees C) is required, resulting in significant power consumption. In this chapter, we report our recent studies on the possibility to exploit the titania photoconduction to develop gas sensor devices working at room temperature. We present the characterization of two different photoconductive Electrospun sensing layers: the first one is composed of titania nanofibres (TiO2 NFs) and the second of TiO2 NFs decorated with Pt nanoparticles (PtNPs) ranging from 5 to 10 nm.