Synthesis of post-polymerizable polyaniline-p-styrenesulfonic acid composite and its application to schottky diode

By using p-stynesulfonic acid to dope polyaniline (PANI), post-polymerizable polyaniline-p-styrenesulfonic acid composite (PANI-p-SSA) was prepared. The composite was synthesized by mixing p-styrenesulfonic acid aqueous solution and polyaniline that was dedoped in NH4OH aqueous solution. The chemical structure of the composite was confirmed by IR and UV/visible spectroscopies and the results indicate that the polyaniline in the composite was re-doped by p-SSA. The composite was partially soluble in N-methyl-2-pyrrolidone and the films were prepared by casting the solution on a glass plate or other substrates. Current-voltage characteristics of the ITO/PANI-p-SSA/A1 diodes (contact area 0.5 cm × 1.0 cm) showed rectification properties. The reverse saturation current density of the junction, JO, was 3.3 × 10−4 A cm−2 and the barrier height, φb, was 0.62 eV.