Nanoporous Nb2O5 hydrogen gas sensor

This work presents the development of gas sensors based on nanoporous niobium oxide (Nb2O5) films for hydrogen gas sensing. Nanoporous Nb2O5 films were successfully synthesized by the anodization of niobium foil in fluoride-organic solvent containing a small percentage of water at 50 °C. These conditions helped to obtain nanovein-like networks with pore diameters of 30-50 nm. After annealing at 440 °C an orthorhombic phase of Nb2O5 was obtained. Contacts of the sensors were then established using platinum (Pt) that also acted as catalytic layers. The gas sensing properties of these nanoporous contacts were investigated for hydrogen gas sensing at different film thicknesses and temperatures.