Current–voltage characteristics of conducting polypyrrole nanotubes using atomic force microscopy

Conducting polypyrrole nanotubes are synthesized by an oxidation polymerization technique using an Anodisc alumina membrane as a template. The morphology is varied from solid rod-like structures to hollow tubes by changing the concentration of the ammonium persulphate (used as the oxidant) solution. The current distribution over the selected area of the membrane and the current–voltage ( I–V ) characteristics of a single nanotube have been investigated by atomic force microscopy. From the current distribution, the lowest wall thickness has been estimated to be and from the I–V characteristics it is seen that the intrinsic conductivity of the tube changes with the wall thickness. The conductivity for tubes with a wall thickness of has been calculated as .