Functional optical materials
Functional optical materials exploded in the eighties with the expansion of soft chemical processes. Doping with organic chromophors gives a strong contribution to the absorption of the hybrid materials, improving their luminescent properties. The presence of organic chromophors, however, requires low temperature of preparation and mild synthesis conditions offered by the sol-gel chemistry.
The preparation functional optical materials based on sol-gel chemistry in Sofia University, is concentrated in the Faculty of Chemistry and Pharmacy. In the groups of Prof. T. Deligeorgiev (Department of Applied Organic Chemistry) and Prof. I. Petkov (Department of Organic Chemistry) optical materials have been synthesized, based on the “antenna effect”, containing complexes of Eu(III) with beta dicarboxyl compounds and cyclodekstrine. In 2005 started the development of sol-gel technology in the in the group of Physical Chemistry of Solids, Assoc. Prof. S. Gutzov (Department Physical Chemistry), functional materials based on Sm(III)-coumarin complexes introduced in silica matrixes were created and described. The group of Prof. Peter Kralchevsky (Department of Chemical Engineering) works in the field of capillary forces and colloidal crystals.
Particle monolayers and multilayers have found numerous applications for producing photonic crystals and quantum dots; photo- and electro-luminescent semiconductor materials; nanostructured surfaces for photo-electrochemical and photo-catalytic processes; optical elements, such as diffraction gratings and interference filters; electronic elements with non-linear electronic and plasmonic properties; substrates for quantum electronic devices, and nanocapacitors; antireflective surface coatings for solar cell panels for conversion of solar energy into electricity, and microlens arrays with applications for beam homogenizers and expanders for full-color displays.