Can dye-sensitized solar cells generate electricity in the dark?

Abstract

Energy harvest requirements for future photovoltaic devices include high efficiency, cost-effectiveness, and persistent power-generation in all weathers. To address this issue, we present here all-weather dye-sensitized solar cells that can generate electricity in the daytime and in the dark by incorporating long persistence phosphors (LPPs) into mesoscopic TiO2 (m-TiO2) photoanodes. When suffered simulated sunlight (air mass 1.5, 100mWcm−2) illumination, the all-weather solar cell having fluorescent-emitting m-TiO2/LPP photoanode yields a maximal photoelectric conversion efficiency of 10.08%. The unabsorbed red and infrared light across dye-sensitized m-TiO2 layer is stored in LPP phosphors, and is subsequently converted into monochromatic fluorescence for persistent dye illumination at dark conditions, yielding a maximized photoelectric conversion efficiency up to 26.69% as well as duration lasting for several hours.