Catalyst-Coated Membrane Heat Treatment for Nafion Oxidation Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Proton exchange membrane fuel cells (PEMFCs) face performance and durability issues due to oxidative corrosion of Nafion-H in the catalyst layer caused by strong oxidizing oxygen radicals, which is exacerbated by the use of external antioxidant additives that can agglomerate and be lost.
Innovation Solution
A catalyst coated membrane is prepared using sodium type resin instead of hydrogen type resin, which enhances the thermal stability and crystallization degree of Nafion-H through heat treatment, thereby improving the membrane's resistance to free radical oxidation corrosion without the need for additional additives.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If external antioxidant additives such as CeO2 and Pt are introduced to reduce strong oxidizing radicals, then the oxidative corrosion of Nafion-H is alleviated, but the additives are prone to agglomeration and loss
Solution Approach 1:
The invention extracts and eliminates the need for external antioxidant additives from the fuel cell system. By using sodium type resin during the membrane preparation process, the Nafion-H crystallization is enhanced intrinsically, providing oxidation resistance without requiring separate additive components that would otherwise be needed
Solution Approach 2:
The invention changes the chemical composition parameter by using sodium type resin instead of conventional hydrogen type resin during membrane preparation. This parameter change enables subsequent heat treatment to effectively enhance Nafion-H crystallization, fundamentally altering the membrane's resistance to oxidation without adding external substances
2Reliability
If heat treatment is applied to enhance Nafion-H crystallization, then the resistance to free radical oxidation corrosion is improved, but the process complexity increases
Solution Approach 1:
The invention performs preliminary action by using sodium type resin during the membrane preparation process itself. This preliminary chemical modification enables the membrane to respond effectively to subsequent heat treatment, transforming what would be a simple heating process into an effective crystallization enhancement treatment that improves oxidation resistance
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The method effectively enhances the resistance to free radical corrosion and durability of membrane electrodes by improving the crystallinity of Nafion-H, ensuring the stability of three-phase reaction sites and maintaining the performance of the membrane electrode.
Implementation Method 1
transferring to an inert atmosphere sintering box for heat treatment to obtain a catalyst coated PTFE membrane
Implementation Method 2
enhances the thermal stability and crystallization degree of Nafion-H through heat treatment
Implementation Method 3
enhances the resistance to free radical oxidation corrosion
Data Source
AI summary
The invention discloses a catalyst coated membrane and preparation method thereof, membrane electrode and fuel cell. The above preparation method includes: firstly, adding sodium type resin to an aqueous-alcohol dispersion of Pt/C catalyst, and stirring and dispersing to obtain a catalyst slurry; secondly, coating the catalyst slurry onto a PTFE membrane, drying at room temperature, and then transferring to an sintering box for heat treatment to obtain a catalyst coated PTFE membrane; thirdly, preparing a proton membrane with catalyst transfer layer by thermocompression transfer of the catalyst coated PTFE membrane and a proton exchange membrane; finally, protonating the proton membrane with catalyst transfer layer to obtain a catalyst coated membrane. The present invention utilizes the great thermal stability of sodium type resin to enhance the crystallization degree of Nafion-H in the catalyst coated membrane through heat treatment, thereby improving the resistance to free radical oxidation and corrosion.