In our previous works, we have made alumina template films and used it for nanowire, nanowhisk, and nanosphere fabrication and molecular aggregation studies. In the present paper, we have combined Al2O3 template and titania (TiO2) NT fabrication processes to achieve an Al2O3/TiO2 NT dye-sensitized solar cell (DSSC) devices. The DSSC structure includes glass substrate, transparent conductive film of ITO, Pt particles serving as the counter electrode, Al2O3/TiO2 NT film, dye, and ITO serving as the working electrode, and the electrolyte is injected into the counter-working interface. Al2O3 template was made by anodization and TiO2 NT was made by sol-gel deposition into Al2O3 template. Al2O3 template has a light, transparence, large surface, good mechanical strength, and flexibility, making it a candidate material for DSSC electrode template. TiO2 NT is a semiconductor with an energy gap that matches up very nicely with N3 sensitized dye. 1. Introduction Due to increasing energy demands and concerns about global warming, scientists are looking for potential renewable energy sources. Because the sun is the most important inexhaustible and clean energy source, efficiently harvesting solar energy to generate electric power using photovoltaic technology beyond silicon systems has undergone rapid development over the past few years. Presently there are several technical schemes for solar cell design, including monocrystalline/polycrystalline silicon solar cells, amorphous silicon solar cells, thin film solar cells, and wet type dye-sensitized solar cells (DSSCs). Of these, monocrystalline silicon solar cells currently have the leading position in the market due to their relatively high transformation efficiency (12–20%). However, since monocrystalline silicon wafers are expensive, manufacturing costs for these cells are high. DSSCs have gradually become more popular due to their lower cost and relatively simple manufacturing process. A DSSC consists of an anode, electrolytic solution, and a cathode. A semiconductor layer is formed on the surface of the anode and photosensitive dyes are absorbed therein. Since the development of low-cost DSSC technology in 1991 by O’Regan and Gr？tzel [1], DSSC has been regarded as a promising candidate for next-generation solar cell design [2]. Traditionally, the electron-collecting layer (anode) of a DSSC is composed of randomly packed TiO2 nanoparticles (NPs). With sunlight irradiated from the transparent anode (front illumination), the best photovoltaic power conversion efficiency (η) of an NP-DSSC device has reached ~11%
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