Incorporating graphene quantum dots boosts thermoelectric performance of PEDOT:PSS films

Conductive polymers, particularly poly(3,4-ethylenedioxythiophene):(styrene sulfonate) (PEDOT:PSS), are gaining significant attention in flexible thermoelectrics due to their excellent flexibility, low thermal conductivity, and structural stability. However, the electrical conductivity of pristine PEDOT:PSS (below 1 S cm⁻¹) limits its power factor. Although polar solvent doping can enhance electrical conductivity, such methods often require complex acid-based post-treatments, compromising material stability and safety. Here, we report highly conductive graphene quantum dot (GQDs)-incorporated PEDOT:PSS films, fabricated via a solvent-free process. The incorporation of trace amounts of GQDs into the PSS and PEDOT matrix enhances the π-π conjugation within the PEDOT matrix, achieving a electrical conductivity of 3027 S cm⁻¹ and a power factor of up to 207.8 μW m⁻¹ K⁻² at room temperature. The solvent-free process preserves film flexibility, making them ideal for flexible thermoelectric devices. These findings present a scalable strategy to enhance the performance of organic thermoelectric materials.