In this work we show dipole-assisted photogated switching by covalent grafting of photoactive molecules to conducting polymers. Photochromic spiropyran molecules were covalently attached to polyaniline (PANI) nanowires via N-alkylation reaction to the quinoic part of PANI. Upon irradiation with ultraviolet light spiropyran transformed to a large dipole containing molecule, merocyanine form. We show that this transformation leads to a substantial (ca. 2 orders of magnitude) increase in conductance of the photochromic PANI nanowires, which were evident by an increase in field-effect mobility and calculated band gap narrowing of the system. Finally, this transformation was found to be fully reversible with no significant photofatigue.

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Composite structures of p-type mesoporous silicon and polyaniline have been fabricated by a one-step electrochemical polymerization process. The composite structure shows good conduction properties and new, intense photoluminescence emission bands that are assigned to polyaniline that penetrates and fulfills the entire volume of the porous silicon matrix quite uniformly. We have found that at room temperature, the reverse bias conductivity of the composite structure is related to transport through the polyaniline network, giving rise to a 5 orders of magnitude larger current relative to that of a reference porous silicon matrix. At low temperatures, the current at both polarities of the bias voltage is carried in the polyaniline network and is related to variable range hopping in three dimensions.

We report on a novel approach to synthesize hybrid nanostructures of meso porous silicon and conjugated organic polymers that are suitable for solar cell applications. Meso‐porous silicon substrates with relatively large pores (∼100 nm) have been exploited for electrochemical polymerization of organic monomers, which were introduced into the porous silicon matrices and electro‐polymerized to create poly‐vinyl‐carbazole (PVK). We present electrical characteristics of a device having relatively thin films of the hybrid medium, which exhibits a photovoltaic mode of operation (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Gold electrode was modified with a 4‐aminothiophenol layer (4‐ATPh) to immobilize DNA. The immobilized DNA served as a template for the alignment of positively charged anilinium ions. The electrochemical oxidation of the anilinium ions resulted in wrapping of the DNA with polyaniline. This polyaniline coated DNA was characterized by cyclic voltammetry (CV), impedance spectroscopy and UV‐VIS absorption spectroscopy.