A high performance methanol gas sensor based on palladium-platinum-In2O3 composited nanocrystalline SnO2

• SnO2-Pd-Pt-In2O3 composite was successfully obtained via a solid-phase reaction method.
• Composite displays ultra-high response to methanol at an operating temperature of 160 °C.
• Composite exhibits good dynamic properties, selectivity, repeatability and stability.
• Composite could be expected for development of an excellent methanol gas sensor.

As a new methanol sensing material, the composite of palladium-platinum-In2O3 composited nanocrystalline SnO2 was successfully obtained by a solid-phase reaction method. The phase composition and the unique structure of as-prepared SnO2-Pd-Pt-In2O3 composite were comprehensively characterized using the techniques such as X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively. The results of gas sensing properties indicate that the sensor based on the as-prepared SnO2-Pd-Pt-In2O3 composite shows the ultra-high response to methanol at an optimal operating temperature of 160 °C when the mass ratio of SnO2, Pd, Pt and In2O3 is 100:0.8:2:30. The gas response toward 100 ppm of methanol reaches as high as 320.73. The detection limit of the sensor is estimated to be 0.1 ppm. The sensor also exhibited good response-recovery properties, selectivity, remarkable repeatability and stability, suggesting its greatly promising application in gas sensing. This work could stimulate an effective means to fabricate methanol sensor with superior performance. At the same time, a possible sensing mechanism of the SnO2-Pd-Pt-In2O3 composite is discussed.

The gas sensor fabricated by palladium-platinum-In2O3 composited nanocrystalline SnO2 exhibits high response, good response-recovery properties, selectivity, remarkable repeatability and stability towards methanol, making it to be promising candidates for practical detectors for methanol.Figure optionsDownload as PowerPoint slide