Study Of The Photoanode And Counter Electrode For Dye-sensitized Solar Cells

Dye-sensitized solar cells (DSSCs) have attracted intense interest due to its low cost and simple preparation procedure. The research and development of the solar cells were reviewed systematically in this dissertation. Specially, the structure, working principle and the influence of components on the photovoltaic performance of the DSSCs were introduced in detail. In order to enhance the photo-to-electron conversion efficiency and reduce the cost of the DSSCs, the main studies of this dissertation are listed below:1. The relationship between the photovoltaic performance and thickness of nanocrystalline TiO2 film of the DSSCs were discussed. The study results indicated that the highest effciency of DSSCs was abtained for a 15μm thickness of nanocrystalline TiO2 film. MgO were added into the TiO2 colloid to fabricate TiO2/MgO composite photoanode in order to suppress the recombination of electron and hole, which increased the photocurrent response of DSSCs. When chenodexoycholic acid (CDCA) was added to the dye bath as a coadsorbent, the unfavorable dye aggregation on TiO2 surface was prevented effectively and the photo-to-electron conversion efficiency of DSSCs were obviously improved.2. A novel composite photoanode for DSSCs was fabricated by electrospinning TiO2 nanofibers onto the TiO2 nanoparticles as a light scattering layer. The reseach of UV–vis absorption spectra and incident photon-to-current coversion efficiency (IPCE) showed light scattering layer could increase the light absorption in the visible region, which raised the photocurrent response of DSSCs. The DSSCs based on composite photoanodes were sensitized by a triphenylamine dyes (SD2) or ruthenium dye (N719) which exhibited a high power conversion efficiency of 8.35, 8.85%, respectively. Meanwhile, the power conversion efficiency of the quasi-solid DSSCs reached about 91% that of liquid electrolyte DSSCs.3. Polypyrrole (PPy) nanopartices with particle diameter of 80-100 nm were synthesized and mixed with graphite to fabricate PPy/Graphite composite counter electrode used in DSSCs. Cyclic voltammetry (CV) analysis of the PPy electrode exhibited excellent catalytic activity for I?/I3? redox reaction. The charge-transfer resistance (Rct) of PPy electrode decreased after the addition of Graphite. The overall energy conversion efficiency of the DSSC based on ruthenium dye (N719) with PPy/Graphite composite counter electrode reached 6.01%, which was 92% of the efficiency of the DSSCs with Pt electrode.