W Tungsten

Gold-directed polypyrrole (PPy) nanoarrays are fabricated by hydrogel-assisted nanotransfer edge printing (HnTEP) and electrochemical polymerization. Gold nanoarrays are fabricated through the HnTEP method, which involves metal deposition, hydrogel etching, and nanotransfer edge printing. By utilizing the well-positioned gold nanostructures, PPy nanoarrays with smooth morphology and controllable dimensions are fabricated through in situ electrochemical polymerization, the results of which are characterized by scanning electron microscopy and atomic force microscopy. A gas sensor based on PPy nanoarrays results in excellent sensing capabilities towards NH3 detection, especially the sensitivity and fast response. This method appears to be general and may aid in the future design and implementation of other active materials which can also be manipulated by the same procedure and serve as functional components for chemical sensing, optoelectronics, biodetection, and other applications.Orientation-controlled growth: We demonstrate a general procedure for the controlled growth of gold-directed conducting polymer nanoarrays through hydrogel-assisted nanotransfer edge printing (HnTEP) and an electrochemical polymerization process. The design is used to fabricate a gas sensor with an ultra-low detection limit down to ppb levels.