Di Li,Yanli Chen,Peng Du,Zhao Zhao,Haifeng Zhao,Yuejia Ma,Zaicheng Sun
Anatase TiO2 film, which is traditionally fabricated by high-temperature annealing of TiOx precursors, has been widely used as an electron collection layer in photovoltaics. In order to avoid the undesired high temperature treatment, in this work, we developed a convenient and moderate procedure to fabricate anatase TiO2 nanocrystal films at room temperature. Ultrafine, clean and high-quality anatase TiO2 nanocrystals have been pre-prepared in a simple solvothermal route and subsequent spin-coating of the nanocrystal dispersion provides a well formed TiO2 nanocrystal film without any further thermal treatment. The characteristics of the TiO2 nanocrystal film, in terms of crystallization phase, film morphology, optical and electronic properties, have been carefully studied, and then a typical [ITO/TiO2/P3HT:PCBM/MoO3/Ag] inverted photovoltaic device using TiO2 nanocrystals as the ECL has been fabricated and exhibits a comparable power conversion efficiency (PCE) of 3.35% to that of the conventional device (3.39% PCE).
To reveal the ways and causes of conversion efficiency enhancement for quantum dot-sensitized solar cells (QDSSCs), chalcopyrite structure CuInS 2 quantum dots (QDs) was synthesized in oil phase by the high temperature hot injection method. Then, QDs were transferred from oil phase to water phase with 3-mercaptopropionic acid as a ligand exchange reagent and loaded inducer of QDs. 3-mercaptopropionic acid coated QDs in water phase were sensitized on TiO 2 nanocrystalline thin films to fabricate QDSSCs. The sensitization time of QDs and pH value in QDs solution are two important factors to affect the loading amounts of QDs and performance of the final assembled QDSSCs. Long-time sensitization of QDs on the TiO 2 porous thin film will cause QDs to agglomerate and stack on the film. The pH of QDs aqueous solution influences the stable existence in solution of QDs and adsorption on the surface of TiO 2 . By balancing the influence of the above two factors, the optimal sensitization condition of CuInS 2 QDs is adsorption in pH = 11 QDs solution for 2 h. In addition, the interface between QD-sensitized TiO 2 porous thin film and FTO is another factor to affect the photoelectric conversion efficiency of QDSSCs. By adding Zn-doped TiO 2 compact layer with high conductivity and electron mobility on QDSSCs to modify this interface, the photoelectric conversion efficiency of QDSSCs was further increased by 66.4 %.
危险品化学品经营许可证（带存储）