Facile fabrication of superhydrophobic flower-like polyaniline architectures by using valine as a dopant in polymerization

A facile method was developed to fabricate superhydrophobic, flower-like polyanline (PANI) architectures with hierarchical nanostructures by adding valine in polymerization as a dopant. The water contact angle of the prepared PANI film was measured to be 155.3 degrees, and the hydrophobic surface of the PANI architectures can be tuned easily by varying the polymerization time as well as valine doping quantity. It is believed that valine plays an important role in not only growth of the hierarchical PANI structures but also formation of the superhydrophobic surface, for it provides functional groups such as -COOH, -NH2 and a hydrophobic terminal group which may further increase intra-/inter-molecular interactions including hydrogen bonding, pi-pi stacking and hydrophobic properties. Similar flower-like PANI architectures have been prepared successfully by employing other amino acids such as threonine, proline and arginine. This method makes it possible for widespread applications of superhydrophobic PANI film due to its simplicity and practicability. (C) 2011 Elsevier B.V. All rights reserved.