Absorption Efficiency Enhancement of Organic Solar Cells by Double Grating Structure

Abstract

A novel surface-plasmon-enhanced structure is proposed to improve the absorption efficiency of organic solar cells in this paper. The PEDOT:PSS-Ag light-trapping structure introduced allows light to be reflected multiple times between the multilayer films, increasing the optical path length of light in the device and the light absorption by the absorption layer. The Ag film in P3HT:PCBM absorption layer can induce surface plasmons, which can enhance the electromagnetic energy around Ag film, improving the light absorption ability of organic solar cells. Based on the finite element method, the COMSOL-RF module is used to simulate the designed structure, and the absorption efficiency, electric field mode distribution and total power loss density distribution at different structural parameters were obtained. The results reveal that the absorption efficiency is more than 80% in the wavelength range of 485 nm to 520 nm in TE mode and more than 85% in the wavelength range of 495 nm to 595 nm in TM mode, providing a reliable basis for the development of high-performance organic solar cells.