TiO2 porous electrodes with hierarchical branched inner channels for charge transport in viscous electrolytes

Yong Zhao, Xianliang Sheng, Jin Zhai, Lei Jiang, Chunhe Yang, Zhongwei Sun, Yongfang Li, Daoben Zhu

Research output: Contribution to journalArticleResearchpeer-review

46 Citations (Scopus)

Abstract

Titanium dioxide (TiO2) photoelectrodes with micro/nano hierarchical branched inner channels have been prepared by an electrohydrodynamic (EHD) technique and assembled to form dye-sensitized solar cells (DSSCs). Excellent penetration of ionic-liquid electrolytes and enhanced light harvesting in the longer wavelength region are realized within the composite-structure electrode, thus a better fill factor (ff) of 75.3 % and higher conversion efficiency (η) of 7.1 % are obtained for viscous ionic-liquid electrolytes compared to pure nanostructured films. Hierarchical branched channels in the photoanodes can efficiently improve the transport properties of redox-active species in viscous electrolytes, which is demonstrated by electrical impedance spectroscopy (EIS). The incident monochromatic photon-to-electron conversion efficiency (IPCE) shows that enhanced light scattering in the composite film is of benefit for light harvesting and thus for solar energy conversion efficiency.

Original languageEnglish
Pages (from-to)856-861
Number of pages6
JournalChemPhysChem
Volume8
Issue number6
DOIs
Publication statusPublished - 23 Apr 2007
Externally publishedYes

Keywords

  • Charge transport
  • Dyes/pigments electrochemistry
  • Light harvesting
  • Nanostructures

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