Nanothin Polyaniline Film for Highly Sensitive Chemiresistive Gas Sensing

This study developed a facile technique for site-specific synthesis of nanometer-thick polyaniline (PANI) film for fabrication of field-effect transistor/chemiresistor sensors. The nanothin film had a thickness of 9-20nm and was of carpet-like morphology offering a highly accessible surface geometry that enhanced gas adsorption and promoted surface reaction/interaction. When applied for sensing of ammonia (NH3) and nitrogen dioxide (NO2), the performance of the nanothin film device was comparable to that of a 1-dimensional (1-D) nanostructure, with a great advantage in ease of processing. Sensing mechanism study indicated electrostatic gating as the dominating mode of sensing.