Swift heavy ion induced modifications in metal conducting polymer composite films

• Effects of O7+ and Ni9+ ion beams on Au–polyaniline composite films.
• SEM shows the formation of clusters with porous structure after irradiation.
• The XRD analysis revealed noticeable change in various parameters.
• Raman spectra show conformational changes after SHI irradiation.
• Results are discussed on the basis of linear energy transfer of the irradiated ions.

Au–polyaniline (Au–PANI) thin films were prepared by an electrochemical process. Au–PANI films were irradiated with 100 MeV O7+ and 120 MeV Ni9+ ion beams with fluences varying from 3 × 1011 ions/cm2 to 3 × 1012 ions/cm2. The effects of heavy ions on the structural, chemical and morphological properties of the composite films were studied by using X-ray diffraction, Raman and scanning electron microscopy techniques. X-ray spectra showed the gradual decrease in the peak intensity after irradiation. The interchain distance, interplanar distance, micro strain, dislocation density and distortion parameters were calculated. The analysis revealed a noticeable changes in these parameters after irradiation for both cases. The results showed the formation of clusters with a porous structure after irradiation. The effect of irradiation was greater in case of 120 MeV Ni9+ rather than 100 MeV O7+ ions due to their high electronic energy loss in Au–PANI. I–V characteristic measurements were carried out as a function of ion fluence. The results are discussed on the basis of linear energy transfer (LET) of the irradiated ions.