Novel cardo poly(arylene ether sulfone)s with pendant sulfonated aliphatic side chains for proton exchange membranes

Covalent Organic Framework Derived Oxygen/Sulfur-Doped Porous Carbon for Robust High-Capacitance Symmetric Supercapacitors

Heteroatom-doped porous carbons (HPCs) have been considered promising electrode materials for supercapacitors due to their improvement of energy density by providing extra pseudocapacity. Covalent organic frameworks (COFs) are obtaining great importance in energy storage because of their designable structure and versatile functionality. Herein, we designed and fabricated oxygen and sulfur dual-doped covalent organic framework (COF) derived HPCs with very high heteroatoms content (up to 25.76 atom%) via a facile coupling reaction. The optimized HPCs exhibit a porous structure with high specific surface area (up to 2835 m2 g-1) along with a high specific capacitance (430 F g-1 at 0.5 A g-1), excellent capacitance retention (96.9 %), and high coulombic efficiency (98.5 %) after 10000 cycles at 5 A g-1. As electrodes for aqueous symmetric supercapacitors, the HPCs exhibits a high energy density of 60 Wh kg-1 at a 250 W kg-1 power density, excellent cycling stability of capacity retention (82.2 %) and a high coulombic efficiency (92.3 %) after 10000 cycles at 10 A g-1, indicating attractive application potential in chemical energy storage. This work establishes a promising strategy for preparation of high heteroatom content HPCs using COFs and demonstrates great potential for energy storage/conversion devices.

Improving the Durability and Performance of Sulfonated Poly(arylene ether)s by Introducing 9,10-Dihydro-9-oxa-10-phosphaphenanthrene 10-oxide Structure for Fuel Cell Application

Polymer electrolyte membranes in which the hydrophilic and hydrophobic domains phase separate exhibit improved properties and stability. Such a phase separation of hydrophilic and hydrophobic domains can be achieved by polymerizing a 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide-bisphenol A (DOPO-BPA) and 1,4-bis(4-fluorobenzoyl)benzene (1,4-FBB) monomer. In this work, sulfonated polymer membranes with various degrees of sulfonation (DS) were prepared and their physicochemical and electrochemical properties were studied. In addition, the effect of molecular structure on the durability of the copolymers was investigated. The sulfonated copolymers were characterized by Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. Then, sulfonated membranes were prepared using these copolymers by the solvent casting method, and their morphologies were investigated by atomic force microscopy. The effect of DS on the thermal, mechanical, and oxidative stabilities, water uptake behavior, and ion-exchange capacity of the membranes was determined. The results showed that compared with the commercially available Nafion 212 polymer electrolyte membrane, the electrolyte membrane based on DOPO-BPA and 1,4-FBB exhibited a lower water uptake and excellent dimensional stability despite having a relatively high ion-exchange capacity. The low water uptake is an important characteristic that ensures the stability of the polymer electrolyte membrane in fuel cell applications.

Accelerated simulation of the degradation process of poly(arylene ether ketone)s containing alkylsulfonated side chains used as a proton exchange mmembrane

The apparent structural degradation of the SPAEKs in Fenton's test is mainly ascribed to the cleavage of the main chains of the polymer.

Influence of phenolphthalein groups on the structure and properties of poly(arylene ether sulfone nitrile)-based anion exchange membranes for fuel cells

Two series of novel poly(arylene ether sulfone nitrile) (PESN) multiblock copolymers are synthesized to prepare anion exchange membranes (AEMs) for alkaline fuel cells.

Highly proton conducting fluorinated sulfonated poly(arylene ether sulfone) copolymers with side chain grafting

A series of new copolymers HPPQSH-XX PS were synthesized from preformed sulfonated ionomers HPPQSH-XX in order to get high proton conductivity along with other excellent properties.

Nanofiber mats electrospun from composite proton exchange membranes prepared from poly(aryl ether sulfone)s with pendant sulfonated aliphatic side chains

The electrospun nanofiber mats revealed high porosity and an interconnected open pore structure. The nanofibers are clearly visible and uniform throughout the composite membrane, which was completely pore-filled.