All organic-based solar cell and thermoelectric generator hybrid device system using highly conductive PEDOT:PSS film as organic thermoelectric generator

• Applicability of PEDOT:PSS film to OTEG for all organic based PV–TE hybrid device was demonstrated.
• The hybridization loss of FF was neglected when the resistance of the PEDOT:PSS film was 1.36 Ω with the thickness of 12.30 μm.
• To further increase the PCE of the hybrid device, PEDOT:PSS thermoelectric modulation with the lower internal resistance is necessary.

We report the fabrication of an all organic-based solar cell and thermoelectric generator hybrid device using an organic solar cell (OSC) and a single highly conductive PEDOT:PSS film as the solar cell and thermoelectric generator (TEG), respectively. The Seebeck coefficient of the single PEDOT:PSS film was measured as 19.8 μV/K. When the two devices were hybridized, hybridization loss (i.e., reduction in FF) caused by the internal resistance of the PEDOT:PSS film used as the organic thermoelectric generator (OTEG) decreased, because of the decreased resistance of the PEDOT:PSS film. The hybridization loss of FF was neglected when the resistance of the PEDOT:PSS film was below 1.36 Ω. The PEDOT:PSS films as OTEG were fabricated by drop-casting of the PEDOT:PSS solution on glass. The temperature difference in the PEDOT:PSS film was 5 °C in the hybrid device. As the resistance of the PEDOT:PSS film was 1.36 Ω, after hybridization, the PCE of the hybrid device was enhanced by the increased open circuit voltage (Voc) generated from the PEDOT:PSS film. The result shows that the PEDOT:PSS film can be applied as an OTEG material for all organic-based solar cell and thermoelectric generator hybrid devices.