Thomas Schmedake

Our research group is interested in the development of silicon containing compounds and materials, especially compounds or complexes in which silicon is used as a substitute for a carbon atom or a transition metal.  Current research focuses on redox-active hexacoordinate silicon complexes, silicon heterocycles, and silicon-based conducting polymers.

Recent highlights:

We have been exploring the interesting redox and spectroscopic properties of hexacoordinate polypyridyl silicon complexes, such as Si(bpy)₃⁺⁴ salts.  These complexes are very redox active and exhibit multiple single-electron reversible reduction waves.  They are also prone to exhibit strong outer sphere charge transfer bands in the visible spectrum.  It is hoped that the tailorable, robust redox properties of these and related complexes could be exploited for energy and molecular electronics applications.  We have also created a dipyridocatecholate analog Si(bpy)₂(dpcat)²⁺ that could be used as a non-innocent redox active ligand for transition metal complexes.  (Polyhedron 2012, 31 (1), 754-758; Inorganic Chemistry Communications 2013, 33 (0), 125-128)

We developed a procedure for synthesizing nearly monodisperse, metal-free and dye-free luminescent colloidal silica particles, and we demonstrated that mesoporous analogs could be used as a substrate for photosensitization of lanthanide ions.  These materials have tunable luminescence properties with a quantum yield around 10%.  Also, they are very stable at high temperatures suggesting potential applications where they may be superior to conventional fluorescent dyes.  (Mater. Lett. 2011, 65 (1), 10-12; Applied Physics Letters 2007, 91, 091909; Chem. of Mater. 2006, 18, (14), 3173-3175)