High Sensitivity, Humidity-Independent, Flexible NO and NH Gas Sensors Based on SnS Hybrid Functional Graphene Ink.

Here, a high sensitivity gas sensing ink based on sulfonated rGO (S-rGO) decorated with SnS is synthesized for room temperature NO and NH detection. This sensing ink demonstrated an excellent sensitivity to ppb-level NO (17% response to 125 ppb) and sub-ppm-level NH (11% response to 1 ppm). The unique absorption properties of SnS improve the sensitivity of S-rGO 4.2 and 55 times to NO and NH, respectively. Besides, the superhydrophobicity of the SnS endows the sensor with exceptional immunity to high relative humidity (RH). Furthermore, the sensors exhibit negligible degradation to NO and less than 15% degradation to NH in a wide range of RH from 30 (ambient humidity) to 90%. More importantly, the obtained full-written ink can be applied to common substrates, such as glass, clothes, and paper, and maintain excellent performance after being bent and twisted by 180°.