Electricity-Driven Post-Functionalization of Conducting Polymers

Electrochemical doping of conducting polymers (CPs) generates polarons (radical ionic species) and bipolarons (ionic species) in their backbone via multi-electron transfer between an electrode and the CP. In the electrochemical polymer reaction (ePR), these generated ionic species are regarded as reactive intermediates for further transformation of the chemical structures of CPs. This electrochemical post-functionalization can easily be used to control the degree of reactions by turning a power supply on/off, as well as tuning the applied electrode potential, which leads to fine-tuning of the various properties of the CPs, such as the HOMO/LUMO level and PL properties. This Account summarizes recent developments in the electrochemical post-functionalization of CPs. In particular, we focus on reaction design for the ePR, with respect to the preparation and structure of the precursor polymers, applicable functional groups, efficient reaction conditions, and electrolytic methodologies.