Nano Energy Research

Artificial photosynthesis: Highly efficient light-harvesting complexes - Multispectral 4D characterization of the energy-transfer processes

Principal Investigator: Prof. Dr. Walter Neu
Collaboration: Prof. Dr. Christoph Lienau, Prof. Dr. Jens Christoffers, Prof. Dr. Karl-Wilhelm Koch

Organic light-harvesting complexes convert light into chemical energy with very high quantum efficiency. This coupling of proteins and chromophores, for example in model complexes such as rhodopsin (receptor protein in the visual process), Bacteriorhodopsin (Bacterial photosynthesis) or chlorophyll, the electronic Coupling between proteins and chromophores results in extremely high
absorption coefficients of nearly 90% and a quantum efficiency of nearly 100%. The focus of this project is the investigation of the relevant elementary processes by means of faster multi-confocal Raman microscopy and high temporal resolution optical Spectroscopy.  These methods allow for a more detailed examination of the symmetry properties of the electronic states. They will furthermore provide insight on the light-energy conversion underlying energy transfer processes, charge transport routes, quantum effects and structural changes at the molecular level.  The high molecular and aggregate-specific selectivity of the methods used are based on the characteristic vibrational spectrum of molecules and therefore requires no Labeling as in fluorescence microscopy. Long-range interactions within the protein environment and effects of communicating cells can be characterized simultaneously, spatially and spectrally.  Through understanding both the Individual molecular processes as well as the transfer paths and the energy conversion an artificial photosynthesis systems, with a similarly high Quantum yield of that in natural systems, can emerge.

M. Schellenberg, M. Kloster, J. Napier, E. Peev, W. Neu, Digital micromirror device based confocal 4D microscopy, Emerging Digital Micromirror Device Based Systems and Applications IV, Michael R. Douglass; Patrick I. Oden (Eds.), Proceeding of SPIE Vol. 8254, 825407 (2012).

M. Schellenberg; E. Peev; M. Kloster; J. Napier; W. Neu, Two-photon time-resolved confocal microscopy using a digital micromirror device, Emerging Digital Micromirror Device Based Systems and Applications III. Proceedings of SPIE, Vol. 7932, 79320H (2011).

M. Schellenberg, E. Peev, M. Kloster, W. Neu, Real Time Visualization of Megavoxel Data in Confocal Microscopy, Photogrammetrie-Laserscanning-Optische 3D-Messtechnik. Beiträge der Oldenburger 3D-Tage 2010. S. 259. Hrsg.: Th. Luhmann/Ch. Müller. Heidelberg, München, Landsberg, Berlin: Herbert Wichmann Verlag (2010)