Mesoporous TiO2 film was prepared at low temperatures, < 130 degrees C, on a conductive indium-tin oxide (ITO)-coated polyethylene naphthalate (PEN) plastic sheet by doctor-blade coating of a binder-free paste consisting of nanocrystalline TiO2 and interparticle binding agent. TiO2-loaded ITO-PEN electrodes were dye-sensitized with Ru bipyridyl complexes to construct photoanodes of plastic dye-sensitized solar cells using iodide/triiodide-based organic redox electrolytes. A solar cell with optimized TiO2 particle size and electrolyte composition yielded highest conversion efficiencies of 5.8% and 6.4% for an incident solar energy of 100 and 23 mW/cm(2), respectively. (c) 2007 The Electrochemical Society.