Preparation of 2D MoSe₂/PEDOT:PSS composite and its thermoelectric properties

Nowadays, inorganic/polymer composites have attracted significant interest in thermoelectric field, since the composite materials usually achieve their respective advantages complementary to each other. In this work, molybdenum diselenide (MoSe₂) was synthesized by a facile hydrothermal method. Solution processible two-dimensional (2D) MoSe₂ nanosheets (NSs) were successfully obtained using dimethylsulfoxide (DMSO) solvent or lithium intercalation procedure. Combined with Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), MoSe₂/PEDOT:PSS composite thin films were fabricated by direct vacuum-filtration method. Thermoelectric properties of composite thin films were investigated systematically and found that 2D MoSe₂ NSs and PEDOT:PSS have the synergistic effect on improving thermoelectric properties. The maximum power factor was calculated to be 48.6 µW m⁻¹ K⁻² with 5 wt% 2D MoSe₂ NSs embedding into PEDOT:PSS matrix, which is almost 69% higher than that of pure PEDOT:PSS. These results demonstrate that 2D inorganic/polymer composite method is one of promising strategies to get high-performance polymer-based thermoelectric composites. (paper)