Light absorption enhancement of organic solar cells with metallic plasmonic nanoparticle

To increase light absorption without altering the thickness of an organic photovoltaic (OPV) device, low band-gap polymer may be employed for efficient light harvesting at long wavelengths. In this work. metallic plasmonic nanoparticles have been utilized to improve light trapping in OPVs. Blend polymer Poly[2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta [2, 1-b;3, 4-b´]dithiophene)-alt-4, 7(2, 1, 3-benzothiadiazole)] (PCPDTBT) and fullerene PC₆₀BM was used as electron donor and electron acceptor for fabrication of organic active layer. The plasmonic effects in OPVs are carried on by employing silver nanoparticle (Ag NP) clusters as back reflector at the bottom of the organic active layer. Remarkable light absorption enhancement offilms by employing NPs was observed by direct incorporation of Ag NPs at the bottom of active layer.