• dye-sensitized solar cells;
  • rapid breakdown anodization;
  • titania nanotubular membranes


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TiO2 nanotubular (NT) membranes with bundle shape morphology were prepared by rapid breakdown anodization (RBA) in fluorine free aqueous electrolytes. The self-assembled nanotube-like materials were detached from the metal foil by immersion in methanolic Br2 solution and the free-standing membranes were successfully transferred on top of transparent conductive electrodes modified by freshly prepared nanoparticulate (NP) titania films. The composite electrodes, after post-annealing at 450 °C, were crystallized under the anatase polymorphism and, then, effectively sensitized by the standard N719 dye (confirmed by micro-Raman spectroscopy under Resonance conditions). The resulting photoelectrodes were incorporated in dye-sensitized solar cells (DSCs) enabling front-side illumination (FSI). The fabricated DSCs attained overall photovoltaic conversion efficiencies of the order of 4.6% under 1 sun (AM 1.5) illumination. The relatively high performance was mainly attributed to the successful packing of the two (NT and NP) layers creating a low resistance interface as well as to the favourable electron transport/recombination dynamics that govern these solar cells.