Improved photovoltaic performance of dye-sensitized solar cells by carbon-ion implantation of tri-layer titania film electrodes

Abstract

TiO2 tri-layer structure films were modified by C-ions implantation for improving the photovoltaic performance of dye-sensitized solar cells (DSSCs), in which the structure of TiO2 changes from rutile to anatase and the sizes of TiO2 particles increase. The optimal concentration of ions implantation for C-implanted cells is 1 × 1015 atom·cm−2, and the maximum conversion efficiency of 5.32 % is achieved (luminous intensity of 1 sun, light irradiance of AM1.5G), which is 25.2 % higher than that of unimplanted cell. The significant improvement in conversion efficiency by carbon-ion implantation is contributed to reducing charge recombination and enhancing the light-harvesting ability, as indicated from incident photon-to-collected electron conversion efficiency (IPCE) and ultraviolet-visible (UV-Vis) measurements. Furthermore, the charge carrier’s lifetime in the tri-layer titania films is prolonged after carbon-ion implantations.