seminars

From Photoinduced Dynamics Towards Materials for Solar Energy Conversion

Physical and Analytical Chemistry Seminar

Lecturer: Maria Wächtler

Date:
22 May 2016 @ 12:30

Location: Faculty Seminar Room

Abstract: One of the largest future challenges is to secure a sufficient and sustainable energy supply for the growing world population. In this respect, the conversion of solar energy into electricity in photovoltaic devices or solar-driven photocatalytic water splitting into hydrogen and oxygen to provide a source of clean and renewable fuel will play a decisive role. For a targeted design of suited molecules and materials for these applications, a detailed understanding of the function immanent light induced processes leading to charge separation and their dependence on structural variations is fundamental. The photoinduced processes in photoactive materials can be addresses by a number of spectroscopic techniques, e.g. steady-state absorption and emission spectroscopy, resonance Raman spectroscopy, fs and ns time-resolved transient absorption spectroscopy, time-resolved emission spectroscopy. The combination of these spectroscopic techniques enables to interrogate the development of the excited systems covering the full time-range starting with the properties of the initially excited state up to the return to the ground state.
This general approach will be illustrated by the example of an investigation of the fundamental photoinduced processes in potential sensitizers for dye sensitized solar cells exploring the possibilities to control the photophysical properties of these systems by structural variations. Further, I will present the results of recent investigations on the source of the excitation wavelength-dependence of the catalytic efficiency of a supramolecular photocatalyst and on the energy transfer processes in multinuclear transition metal complexes with potential application as light-harvesting antennae. Last but not least I will give a short outlook on research activities targeting the exciton and charge-separation dynamics in CdSe@CdS dot-in-rod nanostructures functionalized with catalytically active metal nanoparticles, which have proven to be efficient photocatalysts for hydrogen generation.
Literatur:
1. S. Kupfer, J. Guthmuller, M. Wächtler, S. Losse, S. Rau, B. Dietzek, J. Popp and L. Gonzalez, Physical Chemistry Chemical Physics, 2011, 13, 15580-15588.
2. M. Wächtler, S. Kupfer, J. Guthmuller, J. Popp, L. Gonzalez and B. Dietzek, Journal of Physical Chemistry C, 2011, 115, 24004-24012.
3. S. Kupfer, M. Wächtler, J. Guthmuller, J. Popp, B. Dietzek and L. Gonzalez, Journal of Physical Chemistry C, 2012, 116, 19968-19977.
4. M. Wächtler, S. Kupfer, J. Guthmuller, S. Rau, L. Gonzalez and B. Dietzek, Journal of Physical Chemistry C, 2012, 116, 25664-25676.
5. M. Wächtler, M. Maiuri, D. Brida, J. Popp, S. Rau, G. Cerullo and B. Dietzek, Chemphyschem, 2013, 14, 2973-2983.
6. J. Schindler, S. Kupfer, M. Wächtler, J. Guthmuller, S. Rau and B. Dietzek, Chemphyschem, 2015, 16, 1061-1070.
7. L. Zedler, S. Kupfer, I. R. de Moraes, M. Wächtler, R. Beckert, M. Schmitt, J. Popp, S. Rau and B. Dietzek, Chemistry-a European Journal, 2014, 20, 3793-3799.
8. M. Wächtler, J. Guthmuller, S. Kupfer, M. Maiuri, D. Brida, J. Popp, S. Rau, G. Cerullo and B. Dietzek, Chemistry-a European Journal, 2015, 21, 7668-7674.
9. M. Wächtler, J. Kübel, K. Barthelmes, A. Winter, A. Schmiedel, T. Pascher, C. Lambert, U. S. Schubert and B. Dietzek, Physical Chemistry Chemical Physics, 2016.