Optical Spectra of p‑Doped PEDOT Nanoaggregates Provide Insight into the Material Disorder

Highly
doped poly­(3,4-ethylenedioxythiophene), or PEDOT, is a conductive
polymer with a wide range of applications in energy conversion due
to its ease of processing, optical properties, and high conductivity.
The latter is influenced by processing conditions, including formulation,
annealing, and solvent treatment of the polymer, which also affects
the polymer arrangement. Here, we show that the analysis of the optical
spectra of PEDOT domains reveals the nature and magnitude of the structural
disorder in the material. In particular, the optical spectra of objects
on individual domains can be used for elucidation of molecular disorder
in an oligomer arrangement, which is a key factor affecting the conductivity.