Mesoporous Carbon-TiO₂Beads with Nanotextured Surfaces as Photoanodes in Dye-Sensitized Solar Cells

Mesoporous TiO₂and carbon-TiO₂beads with highly roughened surfaces at the nanoscale were prepared by using triblock copolymer P123 simultaneously as template and carbon source in combination with colloid self-assembly. In addition, their role as modifier of the photoanode in the efficiency enhancement of dye-sensitized solar cells is discussed. Hierarchically organized TiO₂networks can provide fast electron transport paths, and ordered mesopores can enhance light scattering as well as facilitate infiltration of the electrolyte. It was found that there is an optimum loading level of mesoporous TiO₂and carbon-TiO₂beads, that is, 1.0 and 0.5 wt %, with respect to the control P25 TiO₂nanoparticles, respectively, for maximizing the photovoltaic performance. An increase in the photovoltaic performance by up to 21.45 % was achieved by incorporation of mesoporous carbon-TiO₂beads into the conventional photoanode of DSSCs owing to enhanced charge transport and collection effects.