Thin ZnO nanocrystalline films for efficient quasi-solid state electrolyte quantum dot sensitized solar cells

Thin transparent ZnO nanocrystalline films are prepared through a novel facile method based on an amino double edged polypropylene oligomer and zinc precursor. While amines were reacted with acetate groups of zinc acetate starting material, the polypropylene oligomers acted as template for the oxide formation. Different structural properties of the ZnO films were achieved varying the quantity of the oligomer in the starting solution. Spherical aggregated or monodispersed particles were formed with average sizes ranging from 10 to 30 nm. The films were employed in the construction of quantum dot sensitized solar cells using both CdS and CdSe. For first time a quasi solid state electrolyte was applied succeeding a maximum overall efficiency of 4.5% in the case of aggregated particles which could probably act as scattering centers. The quasi solid state electrolyte was a hybrid organic-inorganic material with SiO2 edged groups while no water was used in any step of preparation of the host electrolyte for a polysulfide redox couple. (c) 2012 Elsevier B.V. All rights reserved.