Photoelectric engineering of bifacial dye-sensitized solar cells beyond sunny days.

Abstract The development of weather-independent photovoltaics is a promising strategy for persistently generating electricity in daytime and night. Herein we build a category of multi-energy integrated bifacial solar cells by making long persistence phosphors (LPPs) tailored transparent counter electrodes. The optimized cell with green-emitting transparent polypyrrole-graphene/PtCo achieves a maximized power conversion efficiency of 8.59% under a simulated sun irradiation (100 mW cm−2, air mass 1.5 global) as well as a dark efficiency of 29.68% when ceasing solar illumination. Moreover, the newly launched photovoltaics can persistently generate power lasting for hours in the dark environments. The current work demonstrates a predictable application of photoelectric engineering for persistent energy harvesting free of sun illumination in future. Graphical abstract Image 1 Highlights • Bifacial DSSCs are made by LPP tailored PPy-graphene/PtCo CE. • LPP releases fluorescence to persistently excite dyes when ceasing sunlight illumination. • The DSSCs can persistently generate electricity in the dark. • The newly launched DSSCs yield maximized dark efficiency as high as 29.68%. [ABSTRACT FROM AUTHOR]