Poly (3,4-ethylenedioxythiophene):poly (styrene sulfonate)/tin disulfide composites with enhanced thermoelectric properties

Abstract

Layered metal dichalcogenides have received a lot of interest due to their unique characteristics for energy storage applications. Tin disulfide (SnS2), an emerging semiconducting metal dichalcogenide, has been extensively studied for photovoltaics and photoelectrochemistry. In this work, the thermoelectric (TE) characteristics of tin disulfide-filled poly (3,4-ethylene dioxythiophene): poly (styrene sulfonate) (PEDOT:PSS/SnS2) composites were investigated for the first time. First, ultrasonic homogenization was used to prepare composites with various weight ratios of SnS2 (1, 3, 5, 7 and 10% in terms of polymer content). The existence of SnS2 in the composite structure was confirmed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses, while Fourier-transform infrared-attenuated total reflectance (FTIR-ATR) and ultraviolet-visible (UV-vis) analyses revealed electrostatic interactions between the matrix and filler, as well as increased charge carrier density. The samples' TE performance was assessed using their electrical conductivity, Seebeck coefficient, and TE power factor. The electrical conductivity of pure PEDOT:PSS rose from 0.044 to 0.44 S/cm. The composite samples exhibited negative Seebeck coefficients, indicating n-type characteristics. The Seebeck coefficient of pure PEDOT:PSS increased from 13.4 to -84 mu V/K, while the power factor rose from 7.9 x 10(-4) to 0.17 mu W/mK2.