Synthesis of ionomers for electrochemical energy conversion

Abstract

Due to the ever‐rising atmospheric carbon dioxide levels, there has recently been significant interest in carbon neutral technologies that can convert, store and release energy. Many of these promising technologies, such as fuel cells, electrolyzers, and flow batteries, utilize a polymeric material (ionomer) that allows the transport of ions between electrodes while simultaneously acting as a physical barrier to fuel and current. Perfluorosulfonic acid (PFSA) polymers are the most widely used ionomers for these electrochemical devices due to their excellent proton conductivity and chemical stability. However, PFSA materials lack synthetic flexibility to tune the properties of the ionomer to meet the unique operating conditions of each electrochemical device. To address this issue, hydrocarbon ionomers are explored as a viable alternative to meet the specific operating conditions required of electrochemical devices due to their broad range of polymer architectures and functionalities available to enhance the ionomer performance in the intended device. In this work, hydrocarbon ionomers are synthesized and developed to address the shortcomings of PFSA materials and elucidate the relationships of polymer structures and their conductivity, mechanical properties, and oxidative stability in environments of electrochemical devices.