A nanoscale bio-inspired light-harvesting system developed from self-assembled alkyl-functionalized metallochlorin nano-aggregates

Abstract
Self-assembled supramolecular organization of nano-structured biomimetic light-harvesting modules inside solid-state nano-templates can be exploited to develop excellent light-harvesting materials for artificial photosynthetic devices. We present here a hybrid light-harvesting system mimicking the chlorosomal structures of the natural photosynthetic system using synthetic zinc chlorin units (ZnChl-C6, ZnChl-C12 and ZnChl-C 18) that are self-aggregated inside the anodic aluminum oxide (AAO) nano-channel membranes. AAO nano-templates were modified with a TiO2 matrix and functionalized with long hydrophobic chains to facilitate the formation of supramolecular Zn-chlorin aggregates. The transparent Zn-chlorin nano-aggregates inside the alkyl-TiO2 modified AAO nano-channels have a diameter of ∼120 nm in a 60 μm length channel. UV-Vis studies and fluorescence emission spectra further confirm the formation of the supramolecular ZnChl aggregates from monomer molecules inside the alkyl-functionalized nano-channels. Our results prove that the novel and unique method can be used to produce efficient and stable light-harvesting assemblies for effective solar energy capture through transparent and stable nano-channel ceramic materials modified with bio-mimetic molecular self-assembled nano-aggregates. © 2014 the Partner Organisations.

Citation
Ocakoglu, K., Joya, K. S., Harputlu, E., Tarnowska, A., & Gryko, D. T. (2014). A nanoscale bio-inspired light-harvesting system developed from self-assembled alkyl-functionalized metallochlorin nano-aggregates. Nanoscale, 6(16), 9625–9631. doi:10.1039/c4nr01661k

Acknowledgements
This research has been financially supported by the Scientific and Technological Research Council of Turkey, TUBITAK (Grant: 110M803) and the Polish National Science Center (844/N-ESF-EuroSolarFuels/10/2011/0) in the framework of European Science Foundation (ESF-EUROCORES-EuroSolarFuels-10-FP-006). K. S. Joya acknowledges the Higher Education Commission (HEC), Government of Pakistan, for funding. We are thankful to Prof. Huub de Groot (Leiden University) and Prof. Alfred Holzwarth (Max-Planck Institute, Mulheim, Germany) for the useful discussion.

Publisher
Royal Society of Chemistry (RSC)

Journal
Nanoscale

DOI
10.1039/c4nr01661k

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