In Situ and Operando Studies of Organic Mixed Conductors—Do Charges and Electrolyte Alter the Polymer Microstructure?

Polymeric mixed conductors have elicited much interest lately for their ability to translate ionic fluxes into electronic currents. These materials are being considered in a wide swath of applications ranging from bioelectronics to brain-like computing and electrocatalysis. From the fundamental point of view, it is important to consider how these soft semiconductors interact with the electrolyte (the vehicle of ionic fluxes) and how these interactions alter the materials’ structure due to swelling. Furthermore, volumetric charging with ions allows the materials to reach high charge densities (>10²¹ cm^-3) where charge-induced structural distortions may be pervasive and alter the microstructure. In this talk I will show how using a multi-modal approach that combines optical spectroscopy, x-ray diffraction and TEM, we can unravel these interactions and determine how charge density and electrolyte swelling affect the microstructure and thereby the electronic properties of these materials.