Low temperature preparation of a high performance Pt/SWCNT counter electrode for flexible dye-sensitized solar cells

Highlights: → A flexible Pt/SWCNT electrode was prepared by a vacuum thermal decomposition at 120 deg. C. → The electrode has lower resistance and higher electrocatalytic activity than Pt. → The photoelectric efficiency of flexible cell with Pt/SWCNT electrode reaches 5.96%. → The efficiency is increased by 25.74% compared to the cell with current Pt electrode. - Abstract: A platinum/single-wall carbon nanotube (Pt/SWCNT) film was sprayed onto a flexible indium-doped tin oxide coated polyethylene naphthalate (ITO/PEN) substrate to form a counter electrode for use in a flexible dye-sensitized solar cell using a vacuum thermal decomposition method at low temperature (120 deg. C). The obtained Pt/SWCNT electrode showed good chemical stability and light transmittance and had lower charge transfer resistance and higher electrocatalytic activity for the I3-/I- redox reaction compared to the flexible Pt electrode or a commercial Pt/Ti electrode. The light-to-electric energy conversion efficiency of the flexible DSSC based on the Pt/SWCNT/ITO/PEN counter electrode and the TiO2/Ti photoanode reached 5.96% under irradiation with a simulated solar light intensity of 100 mW cm-2. The efficiency was increased by 25.74% compared to the flexible DSSC with an unmodified Pt counter electrode.