Fabrication of a plastic dye-sensitized solar cell by using the high concentration TiO2 sol through a sol-gel process

Abstract

TiO2 water/ethanol sol capable of interparticle connection was prepared through a sol-gel process and used to the fabrication of organic binder-free TiO2 paste for photo-electrode layer formation of all plastic dye-sensitized solar cells. The average particle size in TiO2 water/ethanol sol was in the range of 27 nm-80 nm and the crystal phase confirmed by XRD was anatase, brookite and rutile. The viscosity of the binder sol showed the strong dependence on the water/alcohol ratio in solution. The organic binder-free TiO2 paste including P-25 powder as the main photoelectrode was prepared by using the TiO2 water/ethanol sol as an inorganic binder and coated on an ITO-PEN (ITO coated on Polyethylene Naphthalate) conductive electrode by a squeeze method. And the processing parameters of TiO2 paste fabrication on the energy conversion efficiency, η, were investigated. The maximum energy conversion efficiency of an assembled plastic dye-sensitized solar cell in this work was found to be 2.58%.