Cobalt sulfide thin films for counter electrodes of dye-sensitized solar cells with cobalt complex based electrolytes

Sang Youn Chae, Yun Jeong Hwang, Jong Ho Choi, Oh Shim Joo

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14 Citations (Scopus)


Recently, a cobalt complex based electrolyte such as [Co(bpy) 3]2+/3+ was suggested to replace the conventional I 3-/I- system because of its potential to provide high open circuit potential and power conversion efficiency in dye-sensitized solar cells (DSSCs). Here, a cobalt sulfide thin film was synthesized by electrochemical deposition and used for a counter electrode. A DSSC with the cobalt sulfide counter electrode exhibits Jsc = 7.228 mA/cm2, which is 13% higher than that with Pt (Jsc = 6.443 mA/cm2), thereby achieving an enhanced power conversion efficiency. Electrochemical impedance spectroscopy measurements indicate that the reduced Warburg diffusion impedance and faster adsorption of [Co(bpy)3] 3+ facilitate the reduction of the cobalt complex.

Original languageEnglish
Pages (from-to)745-749
Number of pages5
JournalElectrochimica Acta
Publication statusPublished - 2013 Nov 20



  • Cobalt complex electrolyte
  • Cobalt sulfide
  • Counter electrode
  • Dye-sensitized solar cells
  • Electrochemical impedance spectroscopy

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Electrochemistry

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