Effect of gold nanoparticles on the structural and optical stability of poly (3-hexylthiophene)

In this work, we have studied the plasmon coupling effect from gold nanoparticles on the structural and optical stability of poly (3-hexylthiophene) (P3HT) films. The P3HT film was deposited on top of a gold nanoparticles covered ITO substrate. An enhancement in light absorption from P3HT, within the visible range, was induced only by the presence of the plasmonic material in high concentrations. Photodegradation rate monitored by FTIR and UV-Vis spectroscopy, have shown that the presence of the plasmonic material improved the structural and optical stability of P3HT. These results were found dependent on the gold nanoparticle concentration. We suggest that the electromagnetic field coupling between adjacent plasmonic nanoparticles in a film results in high extinction cross-section allowing the plasmonic material to act as an optical filter.