Highly enhanced thermoelectric performance of WS₂ nanosheets upon embedding PEDOT:PSS

Abstract

ABSTRACT Two‐dimensional (2D) WS 2 nanosheets (NSs) as a promising thermoelectric (TE) material have gained great concern recently. The low electrical conductivity significantly limits its further development. Herein, we reported an effective method to enhance the TE performance of WS 2 NSs by combining poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate) (PEDOT:PSS). The restacked WS 2 NSs thin film with 1T phase structure obtained by a common chemical lithium intercalation show a high Seebeck coefficient of 98 μV K −1 and a poor electrical conductivity of 12.5 S cm −1 . The introduction of PEDOT:PSS with different contents obviously improve the electrical conductivity of WS 2 NSs thin films. Although a declining Seebeck coefficient was observed, an optimized TE power factor of 45.2 μW m −1 k −1 was achieved for WS 2 /PEDOT:PSS composite thin film. Moreover, the as‐prepared WS 2 /PEDOT:PSS thin film can be easily peeled off and transferred to other substrate leading to a more promising application. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55 , 997–1004