Newly formed carbon nanotubes as counter electrodes for wire-shaped Dye-sensitized solar cells (WDSSCs)

Abstract In this study, the electrodeposition method is employed to treat carbon nanotubes (CNTs) with polythiophene (PTh), polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT), and polyaniline (PANI) polymers, and used them as counter electrodes (CEs) in the structure of wire-shaped dye-sensitized solar cells (WDSSCs). Photoanodes are made of Ti wires that have been anodized and surface treated to produce TiO 2 . We used FESEM images, FTIR, EIS, CV, and Tafel analyses for characterization. Electrochemical methods demonstrate that PEDOT and PANI CEs have higher electrocatalytic activity than that of PTh and PPy polymers, resulting in more current for the WDSSCs. Furthermore, PANI and PEDOT CEs have higher electrocatalytic activity than platinum wire, which is promising. The efficiency of the wire-shaped solar cell based on PEDOT and PANI CEs are 8.51 and 8.58%, which are improved respectively by 7 and 8% compared to the Pt sample, indicating that it could be a promising replacement for this expensive element. Furthermore, the power conversion efficiency test for wire-shaped solar cells using polymer CEs demonstrates their proper performance at various bending angles as well as their high mechanical stability. The long-term stability of wire-shaped solar cells (2000 hours) demonstrates that PANI and PEDOT solar cells have maintained respectively 94 and 88% of their initial efficiency.