Methods to Enhance Electrical Conductivity of PEDOT:PSS-based Electrodes

Abstract This paper extends our prior study on enhancing Poly(3,4-ethylenedioxythiophene) Polystyrene Sulfonate (PEDOT:PSS) electrical conductivity. We explore various methods, including acid treatments, metal nanoparticle doping (Cu and Ag), multiple PEDOT:PSS layer depositions, and mono/multiatomic layer graphene insertion. Our findings reveal that optimizing PEDOT:PSS multilayer depositions and the treatment with nitric acid surpasses the effectiveness of additional methods using metal nanoparticles and graphene. This optimized process not only enhances PEDOT:PSS electrical conductivity but also proves less error-prone, more stable, and more cost-effective than using graphene layers and metal nanoparticles. Optimization factors include spinning speed, etchant concentration, and etching time. Compared to a single-layer PEDOT:PSS of the same thickness, the optimized multilayer PEDOT:PSS treated with nitric acid shows a reduction in sheet resistance from 1 MΩ/sq to 7 Ω/sq. Additionally, we account for film aging to mitigate ambient-induced reliability effects.