Room-temperature low-power hydrogen sensor based on a single tin dioxide nanobelt

Hydrogen sensors have been fabricated from single SnO2 nanobelts synthesized via catalyst-free thermal evaporation. Ohmic contacts were defined on individual SnO2 nanobelts by photolithography and pulsed laser deposition of RuO2. The sensitivity and response time of the sensors, without any catalyst on the surface, to 2% hydrogen at temperatures between 25 and 80°C were measured. Sensitivity greater than 50%, response time <220s, and power consumption <10nW at room temperature were demonstrated.