Two-dimensional SnS nanoflakes: synthesis and application to acetone and alcohol sensors

SnS nanoflakes were synthesized using a solid state reaction method at 600 degrees C and their gas sensing properties were investigated. X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and Transmission Electron Microscopy (TEM) analysis revealed the formation of a pure, polycrystalline, orthorhombic phase of SnS nanoflakes. The response of the SnS nanoflakes sensor to reducing gases such as acetone and alcohols (ethanol, methanol and 1-butanol) was measured from 25 degrees C to 200 degrees C. The response of the SnS nanoflakes sensor was highest for acetone (similar to 1000% at 100 degrees C). It was determined that the optimal operating temperature of the SnS nanoflakes sensor was 100 degrees C for acetone and 1-butanol. Fast response and recovery times of these sensors were observed for all gases. With an increase in temperature from 25 degrees C to 200 degrees C, response and recovery times of the SnS nanoflakes sensor were improved for all gases. Finally, the SnS nanoflakes sensor characteristics have been compared to the characteristics of other metal oxide/sulphide nanostructure sensors reported in previous studies. Moreover, the SnS nanoflakes sensor showed good stability and reproducibility at 100 degrees C for acetone. As acetone in human breath is a marker for diagnosis of diabetes, this work demonstrates a possible use of SnS nanoflakes in diabetes diagnosis.