Pd-doped TiO2 nanofiber networks for gas sensor applications

This work presents a new route to enhance the sensitivity of nanocrystalline TiO2 fibers based gas sensors. Pure and Pd-doped TiO2 nanofiber mats were synthesized by electrospinning and subsequent calcination. Highly porous fibrillar morphology was observed in the resultant nanocrystalline TiO2 fibers. In addition to anatase TiO2 crystallites, tiny (∼2 nm) PdO crystallites were observed in the Pd-doped TiO2 fibers. The sensors using Pd-doped TiO2 fibers showed promising gas sensing characteristics, such as low operation temperature (180 °C) and sufficient gas response (R/Ro = 38 to 2.1 ppm NO2). The techniques outlined here offer new means for preparing novel metal-oxide nanofibers with catalytic dopants.