A kind of anti-degradation enhanced proton exchange membrane and its preparation method

Abstract

The invention belongs to the technical field of fuel cells, and specifically relates to an anti-degradation enhanced proton exchange membrane and a preparation method thereof. The casting liquid containing a vitamin free radical quencher is scraped and coated on the reinforcing material until the film is formed. The proton exchange membrane prepared by the invention has strong degradation resistance. For the first time, the use of vitamin compounds as the free radical quencher carried by the proton exchange membrane is proposed. It is cheap and easy to obtain, has little harm to the environment, and has good free radical The reducibility and anti-free radical degradation performance are improved, and the hydrogen permeation of the proton exchange membrane can be used to reduce vitamins, realize the reuse of free radical quenchers, and also reduce the effect of hydrogen permeation on the membrane electrode aging of fuel cells.

Description

technical field [0001] The invention belongs to the technical field of fuel cells, and in particular relates to an anti-degradation enhanced proton exchange membrane and a preparation method thereof. Background technique [0002] The proton exchange membrane (PEM) in a fuel cell is a solid electrolyte membrane whose function is to isolate fuel and oxidant and to transfer protons (H + ). In practical applications, proton exchange membranes are required to have good chemical and mechanical stability. At present, the commonly used industrial proton exchange membrane is perfluorosulfonic acid membrane. The main chain of fluorocarbons is hydrophobic, and the sulfonic acid end group (-SO3H) of the side chain part is hydrophilic, so microphase separation will occur in the membrane. When the membrane is wet, the hydrophilic phase aggregates together to form a network of ion clusters, which conduct protons. Currently, proton exchange membranes used in vehicles are gradually becom...

AI Technical Summary

Problems solved by technology

The free radical quencher used is CeO 2 or MnO 2 One or two of them, but the problem is that due to the poor compatibility of oxides and ion polymers, in order to fully disperse these metal oxides inside the proton membrane, which is only a dozen microns, the particle size needs to be The size distribution is uniform and the particle size is small, and the purity of the material is extremely high, which greatly increases the overall cost of the proton exchange membrane

However, the basicity and acidity of amines will cause neutralization reactions. Therefore, Schiff base phenolic amines are not stable enough in the strong acidic system of perfluorosulfonic acid proton exchange membranes.

[0004] At present, the application of free radical quenchers is mainly concentrated on variable-valence metal oxide nanoparticles, such as cerium oxide, manganese oxide, titanium oxide, etc., but the perfluorosulfonic acid proton exchange membrane is a strong acid in the presence of water. system, therefore, these variable-valence metal oxides have the risk of dissolution, and the metal ions generated after dissolution will reduce the ionic conductivity and mechanical strength of the proton exchange membrane, and the compatibility with the perfluorosulfonic acid proton exchange membrane is poor

In addition, organic compounds synthesized in the laboratory are used as free radical quenchers, which are expensive and risky to the environment

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