| Polyaniline was synthesized by a combined procedure incorporating various synthesis methods from past studies. Temperature and open circuit potential of the reaction mixture were collected to monitor the reaction progress. As-synthesized polyaniline was found to possess high molecular weight, less branching, cross-linking, and to predominantly consist of linear polymer chains. This polymer was also found to be more stable in solution form. Furthermore, the polymer exhibited improved properties. Metal semiconductor contact devices fabricated using this polyaniline were found to rectify, and the charge transport mechanism occurring in these devices can be modeled using thermionic emission theory. Nanocomposites using polyaniline/single-walled carbon nanotubes and polyaniline/multi-walled carbon nanotubes were fabricated by solution processing techniques. Mechanical and electrical properties of the free-standing films and electronic devices fabricated from these devices indicate enhanced properties compared to neat polyaniline. The dominant transport mechanisms operating in these composite devices were investigated and found to be governed by ohms law in the lower voltage range and space-charge limited conduction in the higher voltage range. These initial results indicate that with further improvements in material consistency and reduction in defect states, the polyaniline/carbon nanotube composite material can be used to fabricate organic electronic devices. |
