Porphyrin cosensitization for a photovoltaic efficiency of 11.5%: a record for non-ruthenium solar cells based on iodine electrolyte.

Dye-sensitized solar cells (DSSCs) are promising for utilizing solar energy. To achieve high efficiencies, it is vital to synergistically improve the photocurrent (Jsc) and the photovoltage (Voc). In this respect, conjugation framework extension and cosensitization are effective for improving the absorption and the Jsc, which, however, is usually accompanied by undesirably decreased Voc. Herein, based on a rationally optimized porphyrin dye, we develop a targeted coadsorption/cosensitization approach for systematically improving the Voc from 645 to 727, 746, and 760 mV, with synergistical Jsc enhancement from 18.83 to 20.33 mA cm(-2). Thus, the efficiency has been dramatically enhanced to 11.5%, which keeps the record for nonruthenium DSSCs using the I2/I3(-) electrolyte. These results compose an alternative approach for developing highly efficient DSSCs with relatively high Voc using traditional iodine electrolyte.