UV assisted room temperature oxygen sensors using titanium dioxide nanostructures

A room temperature oxygen sensor is developed using e-beam evaporated slanted nanorods (NR) of pure titanium dioxide (TiO2) and chromium doped TiO2(Cr-TiO2), showcasing excellent sensing properties with ultraviolet (UV) illumination. The device fabricated using Ti/Au bottom gap electrode with Cr-TiO2 as active material works in a broad range of oxygen concentration from 25 ppm to 100 % with good stability. Fabricated sensors exhibited fast response and recovery times of similar to 3 s and similar to 10 s, respectively. Superior sensing property can be attributed to the enhanced electrical conductivity, excitons created and desorption of water molecules from sensor surface by UV irradiation, facilitating the increased interaction of oxygen molecules with Cr-TiO2 NRs.

Automated summary

A room temperature oxygen sensor is developed using e-beam evaporated slanted nanorods of pure titanium dioxide and chromium doped TiO2, exhibiting excellent sensing properties under UV illumination. The sensor fabricated with Ti/Au bottom gap electrode with Cr-TiO2 as active material works well in a wide range of oxygen concentrations, with fast response and recovery times of around 3 s and 10 s, respectively. The superior sensing properties are attributed to enhanced electrical conductivity, exciton generation, desorption of water molecules, and increased interaction of oxygen molecules with the Cr-TiO2 nanorods facilitated by UV irradiation.