Plasmonic thin-film solar cells with metallic nanostructures

Abstract

A theoretical and experimental study of the plasmonic thin-film solar cell with the metallic nanostructures is presented in this paper. For periodic metallic nanostructures, the finite-difference frequency-domain method is employed to discretize the inhomogeneous wave function for modeling the solar cell. In particular, the hybrid absorbing boundary condition and the one-sided difference scheme are adopted. The parameter extraction methods for the zero-order reflectance and the absorbed power density are also discussed: they are important for testing and optimizing the solar cell design. Furthermore, we propose the phase and attenuation constants conditions of the surface plasmon polariton for lossy materials. For the numerical results, the physics of the absorption peaks of the thin-film solar cell is explained by electromagnetic theory and correspond to the waveguide mode, Floquet mode, surface Plasmon resonance, and the constructively interference between metallic nanostructures. The work is therefore important for the theoretical study and optimized design of the plasmonic thin-film solar cell. Meanwhile, we have also conducted experimental work in plasmonic polymer thin film solar cells by using conventional blend polymer materials of poly(3-hexylthiophene) (P3HT): [6,6]-phenyl-C61 butyric acid methyl ester (PC61BM) and newly synthesized polymers. Our results show that the incident photon to charge-carrier efficiency (IPCE) and current density (J)-voltage (V) characteristics are improved. The power conversion efficiency of the polymer thin fi lm solar cells can be enhanced by about 20-30% through introducing appropriate metallic nanoparticles.