MULTIFUNCTIONAL METAL-ORGANIC FRAMEWORKS FOR NEXT-GENERATION DYE SENSITIZED SOLAR CELLS

摘要

Dye-sensitized solar cells (DSSC) comprised of organic light- harvesting molecules bound to mesoporous titanium dioxide have achieved remarkably high power conversion efficiencies in recent years. The high PCE results from separating light absorption, electron transport, and hole transport to individual materials and independently optimizing these materials. Consequently, the DSSC architecture enables individual components to be independently optimized to a greater extent than bulk heterojunction (BHJ) designs. It is also relatively free of morphology- and microstructure-driven effects that plague BHJ solar cells. Nevertheless, efficiencies ≥20% will likely be necessary to reach the 2020 $1/W installed cost set by the U.S. DOE, driving continued research aimed at discovering new materials. Improving light harvesting by extending dye absorption into the near infrared (800 - 1000 nm), increasing the open-circuit voltage by reducing overpotentials associated with dye regeneration and charge injection, and minimizing charge recombination are strategies likely to have the greatest impact on improving the PCE.