曹国忠：ZnO球聚体,5.4%.pdf

Communications DOI: 10.1002/anie.200704919 Dye-Sensitized Solar Cells Aggregation of ZnO Nanocrystallites for High Conversion Efficiency in Dye-Sensitized Solar Cells** Qifeng Zhang, Tammy P. Chou, Bryan Russo, Samson A. Jenekhe, and Guozhong Cao* As a relatively new class of photovoltaic devices with a particles in an optimal volume ratio. This idea was verified photoelectrochemical system consisting of a dye-sensitized experimentally when TiO2 nanocrystalline films were com- semiconductor film and an electrolyte, dye-sensitized solar bined with large SiO , Al O , or TiO particles.[14–17] By 2 2 3 2 cells (DSSCs) have been regarded as a promising alternative coupling a photonic crystal layer to conventional TiO2 to conventional solid-state semiconductor solar cells. They are nanocrystalline films as the light scatterer, Nishimura relatively cost-effective, are easy to manufacture, and can be et al.[18] and Halaoui et al.[19] also succeeded in enhancing readily shaped with flexible substrates to satisfy the demands the light-harvesting capability of solar-cell photoelectrodes. of various applications.[1,2] A very important feature of DSSCs However, the drawback is that the introduction of larger is the photoelectrode, which includes mesoporous wide-band- particles into nanocrystalline films will unavoidably lower the gap oxide s