Facile fabrication of low-cost low-temperature carbon-based counter electrode with an outstanding fill factor of 73% for dye-sensitized solar cells


International Journal of Energy Research, vol.44, no.4, pp.3160-3170, 2020 (Journal Indexed in SCI Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 44 Issue: 4
  • Publication Date: 2020
  • Doi Number: 10.1002/er.5174
  • Title of Journal : International Journal of Energy Research
  • Page Numbers: pp.3160-3170


Developing chemically inert, electrically conductive, and catalytically active counter electrodes (CEs) to replace conventional Pt‐based ones is highly desirable for dye‐sensitized solar cells. Herein, we reported a facile, cost‐effective, and low‐temperature synthesis pathway to develop carbon‐based CEs. The performance of homemade carbon paste (H‐CP)–based CE (H‐CE) was compared with that of commercial carbon paste (C‐CP)–based CE (C‐CE) and Pt‐based CE (Pt‐CE). The scanning electron microscope (SEM) results showed that H‐CE demonstrated a penetrable surface structure which facilitates the diffusion of electrolyte through the carbon electrode. This phenomenon enhanced the triiodide reduction with respect to C‐CE having a compact structure that limits the electrolyte diffusion. The charge transfer properties and catalytic activities of the investigated devices were explored using electrochemical impedance spectroscopy and Tafel polarization measurements; the obtained results indicated that the device based on H‐CE revealed relatively lower charge transfer resistance and higher exchange current density compared with C‐CE‐based device. The current‐voltage measurements showed that the device based on H‐CE has a power conversion efficiency of 2.70%, which was about 1.6 times higher than that of the device based on C‐CE (1.68%). Furthermore, a fill factor of 73% was achieved for the device based on H‐CE, which outperformed the Pt‐based device (69%) and was among one of the highest values obtained in the literature. Also, a tape adhesion test performed on H‐CP‐coated glass substrate displayed its excellent robustness.