Electrodeposition of Polyaniline/Three- Dimensional Reduced Graphene Oxide Hybrid Films for Detection of Ammonia Gas at Room Temperature

Reliable, sensitive and selective ammonia gas sensing at room temperature is very important for monitoring the environment for hazardous pollutants. In this study, ammonia (NH3) gas sensor is proposed based on polyaniline/three-dimensional reduced graphene oxide (PANI/3D-RGO) hybrid samples, which are loaded on glass substrates by electrochemical polymerization method. The PANI/3D-RGO hybrid samples with different weight percentages of 3D-RGO (weight% =0.05, 0.2, 0.5 and 1) are characterized by field emission-scanning electron microscopy, Fourier transform infrared and X-ray diffraction. The specific surface area is analyzed by the Brunauer-Emmett-Teller (BET) equation. The gas-sensing performances of the fabricated sensors indicate that PANI/3D-RGO (0.2wt. %) exhibits the best response for 50 ppm NH3 gas at room temperature, this sensor response to lower concentrations of NH3 (5ppm, 10 ppm and 25 ppm) too. The PANI/3D-RGO (0.2wt. %) hybrid sensor shows represent response values of about 3.72 and acceptable response and recovery times (98 s and 288 s) to 50 ppm NH3 which is about 4.27 fold higher than that of pure PANI in 50 ppm NH3 gas. The excellent sensing performance of the developed gas sensor can be attributed to the synergetic effects of PANI and 3D-RGO, pi - pi interaction between the two components, efficient increase in hole-like carriers and substantial increase in active sites.