| As a new type photovoltaic cell, dye-sensitized solar cell (DSSC) possesses several advantages over the traditional Si-based solar cells, such as simple fabrication procedures, low cost, and no environmental pollution, which makes it possible for commercial application. Nano-TiO2 film is a very important part in DSSC. In this thesis, photovoltaic performances of DSSCs are improved when W is doped into TiO2. The main results included in this dissertation are summarized in the following:1.Synthesis and characterization of W-doped nano-TiO2Six kinds of W-doped TiO2 nano-particles, with molar ratio of W to Ti at 0.1%,0.2%,0.5%,1%,2%and 5%,respectively, were prepared with a sol-gel method. Characterizations of the W-doped TiO2 nano-particles with XRD, UV, SEM and TEM revealed that W-doping did not affect the particle size and the crystal formation. All the synthesized nano-particles were crystallized in anatase with diameter about 20 nm.2.The fabrication and test of DSSCThe effect of W-doping amount on the performance of DSSCs was studied, and it was found that W-doping could enhance short-circuit photocurrent (Jsc) significantly. The best performance was achieved at the W/Ti ratio of 0.2%,where Jsc was 15.9 mA cm-2, Voc was 0.55 V, FF was 0.59, corresponding to power conversion efficiency (η)5.1% under illumination of AM1.5 simulated solar light (100 mW/cm2). As compared to the DSSC based on non-doped TiO2,JSc andηwere improved by 15% and 21%,respectively. W-doping might cause a positive shift of the conduction band edge of TiO2, which favors electron injection, and thus incident monochromatic photon-to-electron conversion efficiency (IPCE) was improved by 16%.
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