High-performance imidazole-containing polymers for applications in high temperature polymer electrolyte membrane fuel cells
Mu, Tong ; Wang, Lele ; Wang, Qian ; Wu, Yang ; Jannasch, Patric LU
and Yang, Jingshuai
(2024)
In Journal of Energy Chemistry
98.
p.512-523
- Abstract
This work focuses on the development of high temperature polymer electrolyte membranes (HT-PEMs) as key materials for HT-PEM fuel cells (HT-PEMFCs). Recognizing the challenges associated with the phosphoric acid (PA) doped polybenzimidazole (PBI) membranes, including the use of carcinogenic monomers and complex synthesis procedures, this study aims to develop more cost-effective, readily synthesized and high-performance alternatives. A series of superacid-catalyzed polyhydroxyalkylation reactions have been meticulously designed between p-triphenyl and aldehydes bearing imidazole moieties, resulting in a new class of HT-PEMs. It is found that the chemical structure of... (More)
This work focuses on the development of high temperature polymer electrolyte membranes (HT-PEMs) as key materials for HT-PEM fuel cells (HT-PEMFCs). Recognizing the challenges associated with the phosphoric acid (PA) doped polybenzimidazole (PBI) membranes, including the use of carcinogenic monomers and complex synthesis procedures, this study aims to develop more cost-effective, readily synthesized and high-performance alternatives. A series of superacid-catalyzed polyhydroxyalkylation reactions have been meticulously designed between p-triphenyl and aldehydes bearing imidazole moieties, resulting in a new class of HT-PEMs. It is found that the chemical structure of aldehyde-substituted N-heterocycles significantly impacts the polymerization reaction. Specifically, the use of 1-methyl-2-imidazole-formaldehyde and 1H-imidazole-4-formaldehyde monomers leads to yield high-viscosity, rigid and ether-free polymers, denoted as PTIm-a and PTIm-b. Membranes fabricated from these polymers, due to their pendent imidazole groups, exhibit an exceptional capacity for PA absorption. Notably, PTIm-a, featuring methylimidazole moieties, demonstrates a superior chemical stability which maintains morphology and structural stability during 350 h of Fenton testing. After being immersed in 75 wt% PA at 40 °C, the PTIm-a membrane achieves a PA content of 152%, maintains a good tensile strength of 13.6 MPa, and exhibits a moderate conductivity of 50.2 mS cm-1 at 180 °C. Under H2/O2 operational conditions, a single cell based on the PTIm-a membrane attains a peak power density of 732 mW cm-2 at 180 °C without backpressure. Furthermore, the membrane demonstrates stable cycle stability over 173 h within 18 days period at a current density of 200 mA cm-2, indicating its potential for practical application in HT-PEMFCs. This work contributes innovative strategies for the synthesis of advanced HT-PEMs, offering significant improvements in membrane properties and fuel cell performance, thus expanding the horizons of HT-PEMFC technology.
(Less)
- author
- Mu, Tong
; Wang, Lele
; Wang, Qian
; Wu, Yang
; Jannasch, Patric
LU
and Yang, Jingshuai
- organization
- publishing date
- 2024
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Energy Chemistry
- volume
- 98
- pages
- 12 pages
- publisher
- Elsevier
- ISSN
- 2095-4956
- DOI
- 10.1016/j.jechem.2024.07.017
- language
- English
- LU publication?
- yes
- id
- 0a4d8976-434e-4c48-bf6e-f91db7dcac4a
- date added to LUP
- 2024-01-24 10:50:31
- date last changed
- 2024-08-07 02:17:17
@article{0a4d8976-434e-4c48-bf6e-f91db7dcac4a,
abstract = {{<p style="font-family: "Times New Roman"; font-size: medium;">This work focuses on the development of high temperature polymer electrolyte membranes (HT-PEMs) as key materials for HT-PEM fuel cells (HT-PEMFCs). Recognizing the challenges associated with the phosphoric acid (PA) doped polybenzimidazole (PBI) membranes, including the use of carcinogenic monomers and complex synthesis procedures, this study aims to develop more cost-effective, readily synthesized and high-performance alternatives. A series of superacid-catalyzed polyhydroxyalkylation reactions have been meticulously designed between p-triphenyl and aldehydes bearing imidazole moieties, resulting in a new class of HT-PEMs. It is found that the chemical structure of aldehyde-substituted N-heterocycles significantly impacts the polymerization reaction. Specifically, the use of 1-methyl-2-imidazole-formaldehyde and 1H-imidazole-4-formaldehyde monomers leads to yield high-viscosity, rigid and ether-free polymers, denoted as PTIm-a and PTIm-b. Membranes fabricated from these polymers, due to their pendent imidazole groups, exhibit an exceptional capacity for PA absorption. Notably, PTIm-a, featuring methylimidazole moieties, demonstrates a superior chemical stability which maintains morphology and structural stability during 350 h of Fenton testing. After being immersed in 75 wt% PA at 40 °C, the PTIm-a membrane achieves a PA content of 152%, maintains a good tensile strength of 13.6 MPa, and exhibits a moderate conductivity of 50.2 mS cm<sup>-1</sup> at 180 °C. Under H<sub>2</sub>/O<sub>2</sub> operational conditions, a single cell based on the PTIm-a membrane attains a peak power density of 732 mW cm<sup>-2</sup> at 180 °C without backpressure. Furthermore, the membrane demonstrates stable cycle stability over 173 h within 18 days period at a current density of 200 mA cm<sup>-2</sup>, indicating its potential for practical application in HT-PEMFCs. This work contributes innovative strategies for the synthesis of advanced HT-PEMs, offering significant improvements in membrane properties and fuel cell performance, thus expanding the horizons of HT-PEMFC technology.</p>}},
author = {{Mu, Tong and Wang, Lele and Wang, Qian and Wu, Yang and Jannasch, Patric and Yang, Jingshuai}},
issn = {{2095-4956}},
language = {{eng}},
pages = {{512--523}},
publisher = {{Elsevier}},
series = {{Journal of Energy Chemistry}},
title = {{High-performance imidazole-containing polymers for applications in high temperature polymer electrolyte membrane fuel cells}},
url = {{http://dx.doi.org/10.1016/j.jechem.2024.07.017}},
doi = {{10.1016/j.jechem.2024.07.017}},
volume = {{98}},
year = {{2024}},
}