Effects of additives and post‐treatment on the thermoelectric performance of vapor‐phase polymerized PEDOT films

Abstract

Vapor‐phase polymerization (VPP) is an important method for the fabrication of high‐quality conducting polymers, especially poly(3,4‐ethylenedioxythiophene) (PEDOT). In this work, the effects of additives and post‐treatment solvents on the thermoelectric (TE) performance of VPP‐PEDOT films were systematically investigated. The use of 1‐butyl‐3‐menthylinidazolium tetrafluoroborate ([BMIm][BF4], an ionic liquid) was shown to significantly enhance the electrical conductivity of VPP‐PEDOT films compared with other additives. The VPP‐PEDOT film post‐treated with mixed ethylene glycol (EG)/[BMIm][BF4] solvent displayed the high power factor of 45.3 μW m−1 K−2 which is 122% higher than that prepared without any additive or post‐treatment solvent, along with enhanced electrical conductivity and Seebeck coefficient. This work highlighted the superior effect of the [BMIm][BF4] additive and the EG/[BMIm][BF4] solvent post‐treatment on the TE performance of the VPP‐PEDOT film. These results should help with developing the VPP method to fabricate high‐performance PEDOT films. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 1738–1744

Efficient enhancement of the thermoelectric performance of vapor phase polymerized poly(3,4‐ethylenedioxythiophene) films with poly(ethyleneimine)

“…S2–S4). Although σ in this work has a lower value, the S value is similar to some previous reports . After H 2 SO 4 treatment, the electrical conductivity of H‐PEDOT was enhanced to 1000 S cm −1 with a thermopower of 11 μV K −1 .…”

“…VPP‐PEDOT films were prepared by VPP similar to previous reports . The PEDOT films were deposited on a 20 × 20 mm PET substrate, quartz glass, or silicon wafer.…”

“…VPP-PEDOT films were prepared by VPP similar to previous reports. 39,40 The PEDOT films were deposited on a 20 × 20 mm PET substrate, quartz glass, or silicon wafer. Before VPP, the substrates were cleaned sequentially with detergent, deionized water, acetone, and isopropanol in an ultrasonic bath for 30 min.…”

“…Although σ in this work has a lower value, the S value is similar to some previous reports. 40,42,50 After H 2 SO 4 treatment, the electrical conductivity of H-PEDOT was enhanced to 1000 S cm −1 with a thermopower of 11 μV K −1 . 49 To investigate the effect of organic solvents, Figure 5 and Supporting Information Figure S5 show the TE properties of the as-prepared PEDOT films treated with different organic solvents with and without PEI, respectively.…”

In situ Monitoring of Vapor-phase Polymerization and Characterization of Poly(3,4-ethylenedioxythiophene) Thin Films

“…(1)(2)(3)(4)(5) In addition, the thermoelectric power of PEDOT has also been reported. (6)(7)(8)(9)(10) Thermoelectric devices harvest electricity from the heat generated from natural resources and are particularly useful for remote sensing applications in the Internet of Things (IoT). (11)(12)(13) Moreover, thermoelectric materials can be applied to temperature sensors, because they generate electric voltage from a temperature gradient.…”