High sensitivity SnO₂ single-nanorod sensors for the detection of H₂ gas at low temperature

Uniform SnO₂ nanorods were grown by inductively coupled plasma-enhanced chemical vapor deposition without catalysts and additional heating. The SnO₂ nanorods were aligned on a pair of Au/Ti electrodes by the dielectrophoresis method. SnO₂ single-nanorod gas sensors were fabricated by connecting individual SnO₂ nanorods to a pair of Au/Ti electrodes with Pt stripes deposited by a focused ion beam. The sensing properties of the SnO₂ single-nanorod sensor were studied. The SnO₂ single-nanorod sensor could detect 100 ppm H₂ at room temperature with repeated response and showed a large change of resistance, fast response time and good reversibility at an elevated operating temperature of 200 °C. The optimal sensing performance of the sensor is achieved at the operating temperature of around 250 °C.