Get access
Advertisement

Improving Microstructured TiO2 Photoanodes for Dye Sensitized Solar Cells by Simple Surface Treatment

Authors

  • Saquib Ahmed,

    1. Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, 607 Taylor Road, Piscataway, NJ 08854 (USA)
    Search for more papers by this author
  • Aurelien Du Pasquier,

    1. Energy Storage Research Group (ESRG), Rutgers, The State University of New Jersey, 671 US Highway 1, North Brunswick, NJ 08902, USA
    Search for more papers by this author
  • Tewodros Asefa,

    Corresponding author
    1. Department of Chemistry and Chemical Biology and Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, 98 Brett Road, Piscataway, NJ 08854, USA
    • Department of Chemistry and Chemical Biology and Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, 98 Brett Road, Piscataway, NJ 08854, USA
    Search for more papers by this author
  • Dunbar P. Birnie III

    Corresponding author
    1. Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, 607 Taylor Road, Piscataway, NJ 08854 (USA)
    • Department of Materials Science and Engineering, Rutgers, The State University of New Jersey, 607 Taylor Road, Piscataway, NJ 08854 (USA).
    Search for more papers by this author

Abstract

TiCl4 surface treatment studies of porous electrode structure of TiO2 aggregates synthesized using an acidic precursor and CTAB as a templating agent are carried out in order to understand and improve upon recombination kinetics in the photonanode film matrix, together with enhancing the intrinsic light scattering. The key beneficial features of the photoanode included high surface roughness, necessary for superior dye adsorption, nanocrystallite aggregates leading to diffuse light scattering within the film matrix, and a hierarchical macro- and mesopore structure allowing good access of electrolyte to the dye, thereby assisting in dye regeneration (enhanced charge transfer). Pre-treatment of the TiO2 electrodes reduced recombination at the fluorine-doped tin oxide (FTO)/electrolyte interface. The post-treatment study showed enhanced surface roughness through the deposition of a thin overlayer of amorphous TiO2 on the film structure. This led to a notable improvement in both dye adsorption and inherent light scattering effects by the TiO2 aggregates, resulting in enhanced energy harvesting. The thin TiO2 overlayer also acted as a barrier in a core-shell configuration within the porous TiO2 matrix, and thereby reduced recombination. This allowed the hierarchical macro- and mesoporosity of the film matrix to be utilized more effectively for enhanced charge transfer during dye regeneration. Post-treatment of the aggregated TiO2 matrix resulted in a 36% enhancement in power conversion efficiency from 4.41% of untreated cells to 6.01%.

Get access to the full text of this article

Ancillary