Highly Deformable and Stable Gas Sensor Based on Anti-Drying Ionic Organohydrogel for O2 Gas Detection

This paper presented a novel method to prepare organohydrogel-based stretchable O2 sensor with high performance, including good linearity, anti-drying property, low limit of detection (LOD) and long-term stability. A facile solvent replacement approach was devised to partially exchange water with xylitol molecules, generating the stable organohydrogel. Compared with gas sensor based on pristine hydrogel, this organohydrogel-based sensor displayed high water retention, leading to the prolonged life time (>30 days) therefore. In addition, LOD was lowered by 2.45 times to 0.56 ppm. Furthermore, the sensing mechanism was investigated, revealing an electrochemical reaction mechanism occurred at the electrode-hydrogel interface. This work provided a facile method for enhancing the performance of hydrogel-based gas sensor.