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


ALTINKAYA C. , ATLI A. , ATILGAN A. , Salimi K. , YILDIZ A.

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
  • Keywords: commercial carbon paste, dye-sensitized solar cells, homemade carbon paste, low-temperature carbon-based counter electrode

Abstract

© 2020 John Wiley & Sons, Ltd.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.