Efficiency Enhancement in Organic Solar Cells With Extended Resonance Spectrum of Localized Surface Plasmon

The efficiency enhancement of thin film hetero-junction organic solar cells (OSCs) with Au-nanopaticles (Au-NPs) at the interface between the anode and active layers is studied theoretically and experimentally. It is demonstrated that the interface-Au-NPs could effectively extend the spectrum of light absorption enhancement based on the localized surface plasmon, which is revealed by the incident photon-to-current efficiency with photocurrent increased at both the long (λ₀ = 600 ~ 700 nm) and short (λ₀ = 400 ~ 500 nm) wavelength regions. The experiment results also indicate that the efficiency improvement of OSCs is related to the size and concentration of the Au-NPs. The optimized power conversion efficiency enhancement is about 25%.