Electrospun nanostructured TiO2 gas sensors

Titanium-propoxide / poly (vinyl acetate) layers were electrospun on Si substrates fitted with interdigitated Au electrodes. Following the electrospinning process the samples were hot pressed and subsequently calcined at temperatures between 450 and 800degC. Different nanostructured morphologies were produced by modifying the electrospinning and subsequent hot pressing and calcination conditions. The resultant sensor morphologies and chemical composition were examined and their gas sensing properties measured under exposure to traces of NO₂ or CO in dry air at temperatures between 300 and 400degC. The sensors displayed reversible, fast, and remarkably sensitive response demonstrating detection limits in the single ppb level.