Exploring novel methods: Acid treatment, metal nanoparticle doping, and graphene insertion for enhanced electrical conductivity of nm thin PEDOT:PSS films

This study builds upon our previous research aimed at enhancing the electrical conductivity of Poly(3,4-ethylenedioxythiophene) Polystyrene Sulfonate (PEDOT:PSS). We investigate a range of techniques, including acid treatments, doping with metal nanoparticles (Cu and Ag), deposition of multiple PEDOT:PSS layers, and incorporation of mono/multiatomic layer graphene. Our investigations reveal that optimizing the deposition of PEDOT:PSS multilayers and treating them with nitric acid yields superior results compared to alternative methods employing metal nanoparticles and graphene. This optimized process not only enhances the electrical conductivity of PEDOT:PSS but also offers advantages in terms of reduced errors, increased stability, and cost-effectiveness when compared to the use of graphene layers and metal nanoparticles. Optimization parameters such as spinning speed, etchant concentration, and etching time are crucial factors in achieving these outcomes. Compared to single-layer PEDOT:PSS films of the same thickness, the optimized nine-layer PEDOT:PSS treated with nitric acid demonstrates a significant enhancement of conductivity from 0.18 S/cm to 15,699 S/cm. Furthermore, we address film aging to mitigate reliability issues induced by ambient conditions.