PEDOT:PSS light sensor enhanced by localized surface plasomon of gold nano-partcles

In this paper, we used PEDOT:PSS(Poly(3,4-ethylenedioxythiophene) poly(styrenesulfonate)) as light sensing material with enhanced sensitivity by localized surface Plasmon resonance generated by gold nanoparticles . PEDOT:PSS was spin coated on ITO glass substrate and 120 nm of Al were evaporated above the PEDOT:PSS. The electrical properties of PEDOT:PSS was then enhanced after adding the gold nanoparticles between the ITO glass substrate and the film of PEDOT:PSS . We observed that the sample with gold nanoparticles has lower resistance when the samples were lighted. Compared with no illumination, the sample resistance (with naonparticles) decreased about 70%. This is not observed in the sample without gold nanoparticles. And when the density of the gold nanoparticles was increased, the total resistance of the sample was further decreased. When the sample with naonparticles was illuminated at different wavelengths , the total resistance of the sample was distinct. We measured the current intensity at 0.5 voltage at various wavelengths , and we can obtain that the current intensity correlate with the surface Plasmon resonance frequency of gold nanoparticles .