Supramolecular photochemistry research group (SPC-group)
The research activity at the SPC-Group, led by Professors Helge Lemmetyinen and Nikolai Tkachenko (since 2008), can be described as a fundamental study of the photochemistry occurring in solutions and in artificial or self-assembled molecular systems. The key issues are the discovery and development of new materials with desired properties. Systems of interest include molecules capable of transmitting energy, charge or electrons, materials exhibiting electrical conductivity, molecules with unusual optical properties, and structures with optical information storage and processing capability.
The strong background of the group in photochemical research has been created by systematic increase of the knowledge on the theory of photochemistry and by technical development of the photochemistry laboratory, since 1994 at TUT. The laboratory has excellent equipments, especially for measuring ultra-fast photochemical processes.
Special attention have been paid on studies of
- Photo-induced processes in organized system
- Photo-induced generation and transport of charge
- Generation and migration of electronic energy
- Control and tuning of photochemical and -physical properties of molecular components in organized film structures.
Recently reported climate changes demand that the additional energy must be produced by renewable carbon-neutral energy sources. With the background and strategy of the research described above, it was easy for the SPC-group to direct its energies to more practical and ambitious objective: to learn to understand the functioning of organic solar cells. Since 2000 the aim of the research has been to study and develop, with chemical and physical methods, new organic electro- and photo-active materials and structures, which rely on electron donating and accepting molecules and conductive polymers, supramolecular structures, and compounds (porphyrins, phthlocyanines, fullerenes, carbon nanotubes and organic pigments), and demonstrate the operation of an organic solar cell.
Parallel to solar energy research it is utmost important to reveal the crucial factors which control the rates and efficiencies of electron transfer (ET) mechanisms and to develop a quantitative theory for the reactions on the basis of experimental data obtained by time-resolved spectroscopy. This requires experimental investigation of reaction dynamics to distinguish different ET mechanisms and reveal criteria for domination of each of them. The results of this research are supposed to offer new possibilities to control and accomplish ET reactions and to perform new chemical reactions promoted by ET (proton transfer, bonds rearrangements, etc.). This will provide also the novel approaches to the design of molecular devices and nanotechnologies using fine control of ET processes by microenvironment and weak intermolecular interactions in organized molecular systems.
Statistics and lists of publications