Colloidal nanostructured semiconductor materials are explored extensively as photosensitizers and
photocatalysts. To push forward the development of functional materials based on semiconductor
nanocrystals, function immanent exciton and charge separation/recombination dynamics in relation
to structural parameters need to be understood. Factors like composition, structure and dimensions
of the semiconductor particles, the nature of cocatalysts and the type of surface ligands are severely
influencing the efficiencies for solar to hydrogen conversion. By applying time-resolved transient
absorption and photoluminescence spectroscopy we strive to reveal the connections between
structure, charge carrier dynamics and the targeted function. In this presentation, I will give a brief
overview on the results of our studies to illustrate this approach.