Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel Cells
The sluggish commercial application of proton exchange membrane fuel cells (PEMFCs) with low Pt loading is chiefly hindered by concentration polarization loss, particularly at high current density regions. Addressing this, our study concentrates on the ionomer membranes in the cathode catalyst layer...
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MDPI AG
2024-02-01
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| Series: | Polymers |
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| Online Access: | https://www.mdpi.com/2073-4360/16/5/668 |
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| author | Qinjiang Zhang Chao Wang Lina Yu Jiabin You Guanghua Wei Junliang Zhang |
| author_facet | Qinjiang Zhang Chao Wang Lina Yu Jiabin You Guanghua Wei Junliang Zhang |
| author_sort | Qinjiang Zhang |
| collection | DOAJ |
| description | The sluggish commercial application of proton exchange membrane fuel cells (PEMFCs) with low Pt loading is chiefly hindered by concentration polarization loss, particularly at high current density regions. Addressing this, our study concentrates on the ionomer membranes in the cathode catalyst layer (CCL) and explores the potential of incorporating additional hydrophilic or hydrophobic components to modify these ionomers. Therefore, an all-atom model was constructed and for the ionomer and hydrophilic and hydrophobic modifications were implemented via incorporating SiO<sub>2</sub> and PTFE, respectively. The investigation was conducted via molecular dynamics (MD) simulations to predict the morphology and structure of the ionomer and analyze the kinetic properties of oxygen molecules and protons. The simulation results elaborate that the hydrophilic and hydrophobic modifications favor the phase separation and the self-diffusion coefficients of oxygen molecules and protons are enhanced. Considering the hydration level of the ionomer films, hydrophilic modification facilitates mass transfer under low-hydration-level conditions, while hydrophobic modification is more effective in optimizing mass transfer as the hydration level increases. The optimal contents of SiO<sub>2</sub> and PTFE for each hydration level in this work are 9.6% and 45%, respectively. This work proposes a reliable model and presents a detailed analysis of hydrophilic and hydrophobic modifications, which provides theoretical guidance for quantitative preparations of various composite membranes. |
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| institution | Directory Open Access Journal |
| issn | 2073-4360 |
| language | English |
| last_indexed | 2024-04-25T00:21:11Z |
| publishDate | 2024-02-01 |
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| spelling | doaj.art-74dfa6bb661a4d2484bcf5dc880ddd0f2024-03-12T16:53:37ZengMDPI AGPolymers2073-43602024-02-0116566810.3390/polym16050668Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel CellsQinjiang Zhang0Chao Wang1Lina Yu2Jiabin You3Guanghua Wei4Junliang Zhang5SJTU Paris Elite Institute of Technology, Shanghai Jiao Tong University, Shanghai 200240, ChinaZhejiang TangFeng Energy Technology Co., Ltd., Huzhou 313002, ChinaCommercial Vehicle Development Institute, FAW Jiefang Automotive Co., Ltd., Changchun 130011, ChinaInstitute of Fuel Cells, Shanghai Jiao Tong University, Shanghai 200240, ChinaSJTU Paris Elite Institute of Technology, Shanghai Jiao Tong University, Shanghai 200240, ChinaInstitute of Fuel Cells, Shanghai Jiao Tong University, Shanghai 200240, ChinaThe sluggish commercial application of proton exchange membrane fuel cells (PEMFCs) with low Pt loading is chiefly hindered by concentration polarization loss, particularly at high current density regions. Addressing this, our study concentrates on the ionomer membranes in the cathode catalyst layer (CCL) and explores the potential of incorporating additional hydrophilic or hydrophobic components to modify these ionomers. Therefore, an all-atom model was constructed and for the ionomer and hydrophilic and hydrophobic modifications were implemented via incorporating SiO<sub>2</sub> and PTFE, respectively. The investigation was conducted via molecular dynamics (MD) simulations to predict the morphology and structure of the ionomer and analyze the kinetic properties of oxygen molecules and protons. The simulation results elaborate that the hydrophilic and hydrophobic modifications favor the phase separation and the self-diffusion coefficients of oxygen molecules and protons are enhanced. Considering the hydration level of the ionomer films, hydrophilic modification facilitates mass transfer under low-hydration-level conditions, while hydrophobic modification is more effective in optimizing mass transfer as the hydration level increases. The optimal contents of SiO<sub>2</sub> and PTFE for each hydration level in this work are 9.6% and 45%, respectively. This work proposes a reliable model and presents a detailed analysis of hydrophilic and hydrophobic modifications, which provides theoretical guidance for quantitative preparations of various composite membranes.https://www.mdpi.com/2073-4360/16/5/668PEMFCsmolecular dynamics simulationshydration levelhydrophilicityhydrophobicitystructural and transport properties |
| spellingShingle | Qinjiang Zhang Chao Wang Lina Yu Jiabin You Guanghua Wei Junliang Zhang Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel Cells Polymers PEMFCs molecular dynamics simulations hydration level hydrophilicity hydrophobicity structural and transport properties |
| title | Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel Cells |
| title_full | Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel Cells |
| title_fullStr | Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel Cells |
| title_full_unstemmed | Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel Cells |
| title_short | Structural and Transport Properties of Hydrophilic and Hydrophobic Modified Ionomers in Proton Exchange Membrane Fuel Cells |
| title_sort | structural and transport properties of hydrophilic and hydrophobic modified ionomers in proton exchange membrane fuel cells |
| topic | PEMFCs molecular dynamics simulations hydration level hydrophilicity hydrophobicity structural and transport properties |
| url | https://www.mdpi.com/2073-4360/16/5/668 |
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