@article {29148, title = {Spectroscopic detection of halogen bonding resolves dye regeneration in the dye-sensitized solar cell}, journal = {Nature Communications}, volume = {8}, year = {2017}, pages = {1761}, abstract = {

The interactions between a surface-adsorbed dye and a soluble redox-active electrolyte species in the dye-sensitized solar cell has a significant impact on the rate of regeneration of photo-oxidized dye molecules and open-circuit voltage of the device. Dyes must therefore be designed to encourage these interfacial interactions, but experimentally resolving how such weak interactions affect electron transfer is challenging. Herein, we use X-ray absorption spectroscopy to confirm halogen bonding can exist at the dye-electrolyte interface. Using a known series of triphenylamine-based dyes bearing halogen substituents geometrically positioned for reaction with halides in solution, halogen bonding was detected only in cases where brominated and iodinated dyes were photo-oxidized. This result implies that weak intermolecular interactions between photo-oxidized dyes and the electrolyte can impact device photovoltages. This result was unexpected considering the low concentration of oxidized dyes (less than 1 in 100,000) under full solar illumination.

}, issn = {2041-1723}, doi = {10.1038/s41467-017-01726-7}, url = {https://doi.org/10.1038/s41467-017-01726-7}, author = {Parlane, Fraser G. L. and Mustoe, Chantal and Kellett, Cameron W. and Simon, Sarah J. and Swords, Wesley B. and Meyer, Gerald J. and Kennepohl, Pierre and Berlinguette, Curtis P.} }