Size dependence of spherical metal nanoparticles on absorption enhancements of plasmonic organic solar cells

Incorporation of noble metal nanoparticles such as Ag and Au in organic solar cells is one of the promising schemes for plasmonic absorption enhancements. The size of the metal nanoparticles in correlation with optical properties of organic semiconductors is one of crucial parameters for plasmonic enhancements. We analyzed the light scattering and absorption of Ag nanoparticles embedded in an absorbing media using the Mie theory. The size of Ag nanoparticles and the complex refractive index of the absorbing media were adjusted for the light scattering calculations, which reveal that the plasmonic absorption enhancements in the strongly absorbing medium are weakly dependent on the size of Ag nanoparticles and rather sensitive to their volume fractions.