Intrinsic doping and electrostatic complexation of sulfonated poly(3,4-ethylenedioxythiophenes) (PEDOTs)

Self-doped conjugated polymers represent a compelling strategy for achieving efficient electrostatically complexed ionic networks without the need for external dopants. In this work, we present a previously unreported class of sulfonated poly(3,4-ethylenedioxythiophene) (PEDOT) derivatives that exhibit intrinsic self-doping and readily form stable complexes with insulating polyelectrolytes. Notably, we show that even minor variations in the side chain structure, such as a one-carbon difference, have a profound effect on the polymers’ electrical conductivity, structural order, and self-doping level. Using detailed spectroscopic and electrochemical analyses, we reveal how these materials intrinsically stabilize charge carriers and maintain their conductive behavior after complexation. Our findings demonstrate that the self-doped sites act as quasi-permanent ionic–electronic dipoles, creating a robust and adjustable platform for next-generation soft electronic materials. This data includes the raw data of spectroscopy (ultraviolet–visible (UV–vis), mass spectrometry (MS), Fourier-transform infrared (FTIR), nuclear magnetic resonance (NMR)), electronic (cyclic voltammetry (CV), current–voltage (IV) curves of thin films), and thermal properties (differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA)).