Redox Polymer–Based Nano‐Objects via Polymerization‐Induced Self‐Assembly

Abstract

polymer for application as suspension electrode. Indeed, PTMA is able to undergo stable and reversible redox reactions upon electrochemical stimuli. [6] Moreover, it displays high power density with an ultra-fast electron transfer process of 10 −1 cm s −1. [7] Thus, it is also classified as a pseudocapacitive component. This allows PTMA to be widely used as cathode materials in organic radical batteries (ORB). [8,9] Schubert et al. have synthesized water-soluble statistical copolymers containing PTMA and hydrophilic comonomers [10] and have studied their electrochemical properties in water-based and in organic carbonatebased redox flow batteries. [11] While the organic carbonates are widely used due to their good stabilities, the water-based systems reveal better performances as well as positive environmental impact. Furthermore, Schubert and coworkers were able to design a full organic water-based redox flow battery by using water-soluble redox polymers both as catholyte and anolyte. [12] One of the main challenges related to redox polymer-based electrodes remains the relatively low concentration of redoxactive material that can be dissolved while keeping a sufficiently low viscosity to allow the pumping of the liquid electrode in the main electrochemical cell. Decreasing the molar mass of the polymer is not an appropriate option because the redox polymer should not pass through the semi-permeable membrane which is located in the main electrochemical cell. [12] One solution, that allows the dispersion of a high amount of redox polymer without reaching a too high viscosity, consists in tethering the redox polymer chains in a micellar design. Basically, the redox polymer chains could be incorporated into two different compartments of the micellar cargo: the micellar core or the micellar corona. In a previous work, we have designed micellar nano-objects comprising PTMA coronal chains tethered onto a polystyrene (PS) core. These objects were synthesized from PTMA-b-PS diblock copolymers containing a major PTMA block dissolved in carbonate solvents that are selective solvents for the PTMA blocks. [13] The accordingly obtained micelles were successfully tested as catholytes in redox flow batteries. [14] Such a design has the advantage of a good accessibility of the redox-active PTMA chains for redox reactions since they are located in the micellar corona. However, this design has the drawback of being limited to organic solvents for the preparation of the liquid electrodes since both PTMA and PS are hydrophobic groups. The aim of this work is to synthesize micellar nano-objects in aqueous medium containing the redox PTMA polymer. The target is to elaborate an amphiphilic block copolymer containing Redox Polymer Nanoparticles Poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl-methacrylate) (PTMA) redox polymer-based nano-objects are synthesized by polymerization-induced self-assembly with poly[oligo(ethylene glycol) methyl ether methacrylate] and poly[(4-methacryloyloxy)-2,2,6,6-tetramethylpiperidinium chloride] as hydrophili...

Polymeric Active Materials for Redox Flow Battery Application

“…Polymer-based electrolytes enable the application of porous membranes in RFBs with attractive potential for cost reduction and ionic conductivity enhancement. However, the solubility of polymeric molecules is typically lower than that of their corresponding monomers, rendering the PRFB with low specific capacity and energy density. , As the synthesis of highly soluble polymeric redox-active materials remains challenging, the polymer-based RFBs utilizing redox-active colloids or suspensions have emerged in recent years. − In an early report investigating polythiophene as redox-active materials, chemical oxidative polymerization and electrochemical polymerization were used to prepare polythiophene microparticles . A flow cell with polythiophene microparticles as both anolyte and catholyte was assembled.…”

“…Several recent works further expanded the research of polymer colloid/suspension-based RFB. ,,, A significant work was published by Yan and coauthors, in which an all-polymer slurry redox flow battery using suspended microsized polymer particulate active species was reported. The slurry anolyte and catholyte were polyhydroquinone (PHQ) and two polyimides (PI1 and PI2), respectively (Figure a).…”

Redox: Organic Robust Radicals and Their Polymers for Energy Conversion/Storage Devices

“…123,133−135 Based on conventional free radical polymerization, living polymerization techniques have been reported for precise synthesis. 133,135,158,159 Solubility is tunable with copolymers of, for example, polyethylene glycol (NO20), 31 polystyrene (NO21), 126 and other units, 113 which is essential for flow battery applications. Introducing anthraquinone to the polymer mediated the n-type redox of TEMPO (NO22).…”

Engineering bioinks for 3D bioprinting

“…chemically driven [235][236][237][238][239], redox reactive species [240,241], light-induced [242], and magnetic field-induced [243], and could potentially allow to closely mimic natural tissue generation. However, such strategies still have a long road ahead before making their way into biofabrication and bioprinting.…”