Semitransparent Dye-Sensitized Solar Cell with 11% Efficiency and Photothermal Stability

Overcoming the excited-state quenching and interfacial charge recombination is of far-reaching significance for achieving dye-sensitized solar cells (DSSCs) with high efficiency and durability. Cografting a wide-energy-gap adsorbent with a low-energy-gap photosensitizer on mesoporous titania film is an important tactic to address these issues and simultaneously increases the transparency of DSSC to a certain degree, which is appealing for see-through and colorful building-integrated photovoltaics. We herein report a powerful coadsorbent Y1, which is grafted along with the middle-energy-gap organic dye C268 on titania film for see-through DSSCs with a recorded efficiency of 11% under the AM1.5G conditions. The cografting-induced increase in efficiency benefits from the improved yields of electron injection and hole injection, as well as the slower interfacial charge recombination kinetics. More importantly, the cell is endowed with an excellent efficiency retention rate of 90% after 1000 h of full sunlight soaking at 60 °C.