SnO₂ quantum dots decorated on RGO: a superior sensitive, selective and reproducible performance for a H₂ and LPG sensor

We report the H₂ and LPG gas sensing behavior of RGO/SnO₂ QDs synthesized by a surfactant assisted hydrothermal method. The RGO/SnO₂ QD based sensor shows a high response of ∼89.3% to H₂ and ∼92.4% to LPG for 500 ppm test gas concentration at operating temperatures of 200 °C and 250 °C, respectively. Further, the RGO/SnO₂ QD based sensor shows good selectivity for H₂ and LPG in the presence of other interfering gases such as ammonia, chloroform, toluene, benzene, acetone, n-butylacetate, acetic acid and formic acid. We observed that the gas response to H₂ is 29.8 times higher than that to acetic acid whereas the gas response to LPG is 17.8 times higher than that to formic acid. Long-term analyses have also been performed to demonstrate the reproducible nature of the RGO/SnO₂ QD based sensor over passing time which shows excellent reproducibility.