Effect of Solvent Variations in the Alcothermal Synthesis of Template-Free Mesoporous Titania for Dye-Sensitized Solar Cells Applications

PLoS One. 2016 Oct 14;11(10):e0164670. doi: 10.1371/journal.pone.0164670. eCollection 2016.

Abstract

A series of 14 mesoporous titania materials has been synthesized using the simple alcothermal template-free method and various alcohols, such as methanol, propanols and butanols, as solvents. All materials were characterized by both wide and small angle XRD, which exhibited the anatase phase with short-range ordered mesoporous structure that is still forming during post synthetic temperature treatment in most of the investigated materials. Nitrogen adsorption-desorption isotherms confirmed the mesoporous structure with surface area ranging from 241 to 383 m2g- 1 and pore volumes from 0.162 to 0.473 m3g-1, UV-Vis diffuse reflectance showed the redshift of the absorption edge and the bandgap decrease after post synthetic calcination of the materials presented. The TEM, FT-IR, DTA and TG measurements have been made to well characterize the materials synthesized. The mesoporous samples obtained were applied as anode materials for dye-sensitized solar cells and showed good activity in photon-to-current conversion process with efficiency values ranging from 0.54% to 4.6% and fill factors in the 52% to 67% range. The photovoltaic performances were not as high as those obtained for the materials synthesized by us earlier employing ethanol as a solvent. The differences in the electron lifetime, calculated from electrochemical impedance spectroscopy results and varying between 4.3 to 17.5 ms, were found as a main factor determining the efficiency of the investigated photovoltaic cells.

MeSH terms

  • Adsorption
  • Alcohols / chemistry
  • Coloring Agents / chemistry
  • Microscopy, Electron, Transmission
  • Nitrogen / chemistry
  • Porosity
  • Solar Energy*
  • Solvents / chemistry*
  • Spectroscopy, Fourier Transform Infrared
  • Thermogravimetry
  • Titanium / chemistry*
  • X-Ray Diffraction

Substances

  • Alcohols
  • Coloring Agents
  • Solvents
  • titanium dioxide
  • Titanium
  • Nitrogen

Grants and funding

Fondazione Cariplo (http://www.fondazionecariplo.it) and Regione Lombardia (www.regione.lombardia.it) have funded the SmartMatLab project (users2.unimi.it/smartmatlab/wordpress grant No. 2013-1766) and MZ and ES were employed to this project and the lab facilities were used in some measurements in this work. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.