Enhanced Thermoelectric Performance of PEDOT:PSS-Based Composites by Constructing Sequential Energy-Filtering Interfaces and Energy Barriers

Among all reported organic thermoeletric materials, poly(3,4-ethylenedioxythiophene):poly(styrenensulfonate) (PEDOT:PSS) has drawn extensive attention owing to its high electrical conductivity. However, the Seebeck coefficient of PEDOT:PSS needs to be enhanced without sacrificing electrical conductivity. As one approach, modulating the energy filtering effect at the component interfaces can enhance the Seebeck coefficient with only a slight reduction in electrical conductivity. In this presentation, I will report an effective strategy to significantly enhance the thermoelectrical properties of PEDOT:PSS by integrating core-shell PEDOT/polypyrrole (PPy) nanowires to form multiple sequential interfaces and enabling more effective energy filtering process in between. By tailoring the energy barriers among PEDOT/PPy/PEDOT:PSS interfaces, the Seebeck coefficient of the PEDOT:PSS composites was increased by ∼46% with only a slight decrease in electrical conductivity. As a result, a significant improvement of over 85% in power factor was achieved compared with pristine PEDOT:PSS.