Hydrophilic Channel Volume Behavior on Proton Transport Performance of Proton Exchange Membrane in Fuel Cells

Abstract

Inadequate water balance causes water flooding in a fuel cell, leading to performance degradation. The hydrophilic channel volume is crucial to the proton conductivity of PEM, especially under a high water concentration gradient. Herein, the volume of the hydrophilic channel was controlled and optimized through adjusting the collocation of resins with different side-chain lengths, with the length acting as a key parameter for the in-depth research on the proton conductivity performance of PEMs. Membranes with different hydrophilic channel volumes were prepared and suggested that the volume of the hydrophilic channel boosted as the increase of the length gap between the matched side chains, which would benefit to proton conductivity of membrane. This study provides guidance for the structural design of proton exchange membrane with cell-flooding resistance and efficient proton conduction at a high water concentration gradient.

Phosphate-grafted polyethyleneimine-induced multifunctional cerium oxide as an antioxidant for simultaneously enhancing the proton conductivity and durability of proton exchange membranes

“…To understand the underlying mechanism of CeO 2 @Ph-PEI-based PEMs that simultaneously combine high proton conductivity and strong chemical durability, we have dissected the microstructure of the prepared membranes by Small Angle X-ray Scattering (SAXS) and Atomic Force Microscopy (AFM) techniques. [44] As shown in Fig. 3b, the SAXS patterns of all the as-prepared membranes displayed ionomer characteristic peaks.…”

Phosphonate poly(vinylbenzyl chloride)-Modified Sulfonated poly(aryl ether nitrile) for Blend Proton Exchange Membranes: Enhanced Mechanical and Electrochemical Properties

“…Clean hydrogen energy and high-energy density fuel cells are crucial for global energy sustainability [1][2][3]. The quality of proton exchange membranes, which serve as the conduction medium of fuel cells, plays a vital role in determining their performance and lifetime [4][5][6][7]. Currently, perfluorinated sulfonic acid polymers are the preferred choice for proton exchange membranes due to their excellent physical and chemical stability [8][9][10].…”

Molecular Dynamic Simulations of Proton and Water Transport Mechanism in a Nafion Pore

“…[8] The amphiphilic structure of perfluorosulfonic acid (PFSA) membranes form water channels for effective phase separation between extremely hydrophilic side chains and hydrophobic backbones. [9] In these channels decorated by hydrophilic side groups, protons combine with water molecules to form dynamic species consisting of water molecule aggregates (e.g.,…”

“…[ 8 ] The amphiphilic structure of perfluorosulfonic acid (PFSA) membranes form water channels for effective phase separation between extremely hydrophilic side chains and hydrophobic backbones. [ 9 ] In these channels decorated by hydrophilic side groups, protons combine with water molecules to form dynamic species consisting of water molecule aggregates (e.g., H 3 O + , H 5 O 2 + (Zundel ion), or H 9 O 4 + (Eigen ion)) for transmission. [ 10,11 ] The structural factors affecting the proton diffusivity include side chain separation, pore size, side chain length, side chain species, channel distortion, etc.…”