Conducting Polymers As Electrochemical Energy Storage Platforms

Abstract

Solving the energy crisis and putting a halt to climate change is the greatest challenge of this century. In order to solve the energy crisis, harvesting energy from renewable sources needs to be economically and technologically feasible. Renewable energy sources are intermittent, but for our society to keep functioning uninterrupted access to electricity is a must. For this uninterrupted access, electrochemical energy storage (EES) is needed to provide energy when the renewable source is not available. Among EES, batteries and electrochemical capacitors (ECs) have shown the most promise, providing higher energy and power densities than other EES. In this publication conducting polymers as electrode materials are demonstrated to have improved performance over commercially available electrodes for EES applications. Conducting polymers are proven to be both electrocatalysts towards the redox reactions of organosulfur compounds and high gravimetric capacity electrode materials. Studies of the origin of the electrocatalytic effect yielded poly-3,4ethylenedioxythiophene (PEDOT) as the best electrocatalyst. The idea of incorporating small redox active substituents (RAS) is proven effective and the understanding of the electropolymeriation reaction of RAS-CP is achieved. A RAS-CP that had practical capacities of 80 mAh/g was designed; this capacity was higher than any other CP reported in the literature to date. Finally, the post-polymerization reaction was proven effective for the synthesis of RAS-CPs yielding polymers with enhanced capacity retention.