Characterisation of polypyrrole nano-films for membrane-based sensors

Thin polypyrrole nano-films were formed chemically by interfacial polymerisation. An interesting feature of this chemical synthesis is that compact ultra thin polypyrrole films of 50 nm thickness doped with sulphate are obtained by a simple technique, although, films grown in the presence of different dopants were thicker (100 nm). Oxidative polymerisation allowed reproducible synthesis of very thin films in a very short time. Assessment of the surface of the films by atomic force microscopy indicated a strong influence on experimental conditions such as pH, nature and size of the dopant ions.