Influence of Nanoporous Oxide Substrate on the Performance of Photoelectrode in Semiconductor-Sensitized Solar Cells

Oxide substrates in semiconductor-sensitized solar cells (SSSCs) have a great impact on their performance. TiO2 has long been utilized as an oxide substrate, and other alternatives such as ZnO and SnO2 have also been explored due to their superior physical properties over TiO(2)w. In the development of high-performance SSSCs, it is of significant importance to understand the effect of oxides on the electron injection and charge recombination as these two are major factors in dictating solar cell performance. In addition, elucidating the relationship between these two critical processes and solar cell performance in each oxide is critical in building up the basic foundation of SSSCs. In this study, ultrafast pump-probe laser spectroscopy and open-circuit decay analysis were conducted to examine the characteristics of three representative oxides (TiO2, ZnO, and SnO2) in terms of electron injection kinetics and charge recombination, and the implication of results is discussed.I thank Prof. P. V. Kamat for helpful discussion. The experiments were carried out at Radiation Laboratory, University of Notre Dame, which is supported by the Department of Energy, Office of Basic Energy Sciences. I acknowledge the research fund provided by HanyangUniversity (HY-2010-N)