Synthesis Of Polyaniline Micro/Nanostructures And Its Properties

Micro/nanostructured conducting polyaniline (PANI) is one of the most widely investigated owing to their highly conjugated molecular structure, its straightforward polymerization, chemical stability, relatively high conductivity. In this article, doped PANI material with different morphologys has been successfully synthesized by using different polymerization methods. The PANI material in gas sensors and electrical catalysis applications were systematic studied and the main achievement are summarized as follows:1. PANI nanorods and hollow-microspheres have been successfully prepared by using copper wires and rings, respectively, and the structure and morphology were characterized. Different morphology of the resulting products can be obtained and controlled by using corresponding different shape of the objects. Prompted by the high surface areas, small diameter, and porous structure of the prepared PANI, the sensitivity was prepared.2. A route for producing PANI nanotubes which is using the inner eggshell membrane as a template is demonstrated. A series of experimental results indicate that the pore size of the template plays a key role in the formation of the PANI nanotubes. By imaging the template before, during and after the polymerization, a possible formation condition and process of PANI nanotubes is proposed. Meanwhile, fiber mats imitating eggshell membrane, electrospun poly(vinyl alcohol) fiber mats, are successfully used as a template for synthesizing PANI nanotubes in the same polymerization process. The high surface areas, small diameter, and porous nature of the PANI nanotubes give significantly better performance in both gas sensitivity and time response.3. Silver/PANI composite nanotubes have been successfully synthesized via a self-assembly process assisted by excess ammonium persulfate and silver nitrate as oxidant without using any acid molecule reagent or hard template. The silver/PANI composite nanotubes exhibit higher electrocatalytic activity toward reduction of dopamine than pure PANI. Furthermore, the high surface area, small diameter, and porous nature of the silver/PANI composite nanotubes and the introduction of the silver nanoparticles give significantly better performance in both gas sensitivity and time response.4. Single-crystalline PANI with dendritic micro/nanostructures has been synthesized by a vapor-phase polymerization method. During this process, the slow polymerization rate and low reactant concentration play crucial roles in confining the growth of single-crystalline PANI with dendritic morphology. In addition, the PANI crystal exhibits an excellent reversibility to NH3 gas, which shows potential applications in the area of sensor development.