Growth and alignment of polyaniline nanofibres with superhydrophobic, superhydrophilic and other properties

Polyaniline nanofibres can be prepared by a number of methods based on chemical oxidative polymerization 1 , 2 , 3 , 4 , 5 , 6 , 7 and in situ adsorption polymerization 4 , 5 , 6 . However, the lack of alignment in these nanostructures makes them unsuitable for many applications. Here, we report a simple approach to chemical oxidative polymerization that can control the growth and simultaneous alignment of polyaniline nanofibres grown on a range of conducting and non-conducting substrates in a wide variety of sizes. The diameters of the tips of the nanofibres can be controlled within the range 10–40 nm, and the average length can be controlled within the range 70–360 nm. Moreover, the coatings display a range of properties including superhydrophilicity and superhydrophobicity. Such nanostructured coatings may be useful for applications such as anti-fog coatings, self-cleaning surfaces, DNA manipulation, transparent electrodes for low-voltage electronics, and chemical and biological sensors.