Enhancing Light Absorption in Photoactive Layer of Organic Solar Cells Using Plasmonic Copper Nanorods

Bulk-heterojunction organic solar cells have gained much interest due to low cost and large-scale fabrication. However, their power conversion efficiency (PCE) suffers from charge recombination, limiting commercialization. In this study, the plasmonic resonance of colloidal copper nanorods (CuNRs) have been employed to enhance light absorption inside phenyl-C₆₀-butyric acid methyl ester: poly(3-hexylthiophene) (P3HT:PCBM). The CuNRs with diameter of 20.60 ± 0.54 nm and length of 57.81 ± 1.5 nm induced transverse and longitudinal absorption peaks at 450 and 680 nm respectively inside P3HT:PCBM. The peaks intensify with increase in concentration of CuNRs. The incorporation of CuNRs improved the PCE of a ITO/PEDOT:PSS/P3HT:PCBM:CuNRs/Ag device by 3,78%. CuNRs in P3HT:PCBM has the potential to improve power conversion efficiency of organic solar cells by inducing plasmonic resonance.