JCAP Seminar

Sensitizing large band gap semiconductors to sub-bandgap light began with the development of photography and has recently been applied to solar energy conversion. Single crystal semiconductor electrodes provide an ideal experimental system for the elucidation of the models and parameters that control light absorption, charge separation, and transport at semiconductor/liquid interfaces. The single crystal experimental system is much less complex than its nanocrystalline counterpart and the study of well-defined crystallographic surfaces allows for more definitive conclusions to be made concerning the relation between sensitizer attachment and surface structure and the sensitizer's performance. I will give a historical perspective of our work on single crystal semiconductor electrodes including some recent work where we have measured and modeled the doping level dependence of sensitized photocurrents for several dyes adsorbed on rutile single crystals. The use of quantum dots as sensitizers will also be discussed including our measurement of multiple exciton generation and collection.