A novel electropolymerization method for Ppy nanowire-based NH3 gas sensor with low contact resistance

One-dimensional (1-D) nanostructures of conducting polymers are a superior choice in chemical sensors and biosensors due to possibility of constructing sensors with higher sensitivity and fast detection. Here we report a new method for fabricating two electrode sensing device with low contact resistance by electrochemical synthesis of polypyrrole (Ppy) nanowires. This approach shows a new patterning technique which makes the addressable Ppy nanowires on the pre-patterned sub-Ni nanowires, in which large contact area between metal electrodes and Ppy significantly reduced the contact resistance. Performance of Ppy nanowire-based gas sensors for the detection of sub-ppm level concentrations of ammonia (NH3) gas is investigated.