Ultrafast excited state dynamics of iridium(III) complexes and their changes upon immobilisation onto titanium
Stefanie Tschierlei1, Antje Neubauer2, Nils Rockstroh3
1Institute of Physics, University of Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany. stefan.lochbrunner@uni-rostock.de and Institute of Organic Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany. stefanie.tschierlei@oc.uni-stuttgart.de.
Abstract:
Time-resolved spectroscopy was applied to investigate the excited state dynamics of two heteroleptic Ir(III) complexes with the general formula [Ir(C^N)2(N^N)](+), where C^N and N^N represent different cyclometalating and diimine ligands, respectively. The excited state relaxation is influenced by the ligand substitution as well as the light polarisation. Vibrational relaxation occurs in the sub-ps timescale and interligand charge transfer results in polarisation dependent signal dynamics with a time constant of about 30 ps. Electron injection from the iridium dye to TiO2 is analysed with respect to potential applications in solar energy conversion.
