Molecular Engineering of High-Performance Anion Exchange Membranes for Fuel Cells and Water Electrolyzers
Dr Nanjun Chen, Laboratory of Inorganic Synthesis and Catalysis (LSCI), Institute of Chemical Sciences and Engineering (ISIC), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne 1015, Switzerland
Abstract
Anion exchange membranes (AEMs) have attracted tremendous research interest in cost-effective alkaline energy devices such as AEM fuel cells (AEMFCs) and AEM water electrolyzers (AEMWEs) due to the feasible utilization of earth-abundant non-noble catalysts. AEM-based energy devices are intended to supersede costly platinum-group-metal (PGM)-containing acidic energy systems and provide a low-cost pathway for sustainable energy conversion and utilization [1]. However, insufficient ion conductivity and poor chemical & mechanical stability of AEMs have significantly impeded the development of AEMFCs and AEMWEs. Our research is focused on exploring highly conductive and durable AEMs and ionomers using aryl ether-free poly(aryl-co-aryl piperidinium) (c-PAPs) copolymers [2-6]. Compared with common AEMs, c-PAP-based AEMs possess outstanding ion conductivity (>150 mS cm-1), mechanical properties (tensile strength>80 MPa), and chemical stability (1 M NaOH @ 80 oC >2,000 h). c-PAP ionomers also display high ion-exchange capacity (IEC), low ionomer adsorption on PGM catalysts, and high electrochemical performance. Moreover, we have applied c-PAP AEMs and ionomers to both AEMFCs and AEMWEs. c-PAP-based AEMFCs reached outstanding peak power density (PPD) of 2.67 W cm-2 in H2-O2 at 80 oC. On the other hand, c-PAP-based AEMWEs achieved outstanding current density of 7.69 A cm-2@2.0 V, and the cells can be run stably greater than 1,000 h under 0.5 A cm-2 at 60 oC without any voltage decay. The present AEMFCs and AEMWEs exceed the power density and current density of state-of-the-art proton exchange membrane fuel cells (PEMFCs) and proton exchange membrane water electrolyzers (PEMWEs), respectively. Our ongoing work is to develop high-performance AEMFCs and AEMWEs with PGM-free catalysts.
Reference
[1] N. Chen and Y. M. Lee*. Trends in Chemistry, 2022, 4, 236-249.
[2] N. Chen#, S. Y. Lee#, S. Y. Lee*, Y. M. Lee*, et al. Energy Environ. Sci., 2021, 14, 6338-6348.
[3] N. Chen#, C. Hu#, Y. M. Lee*, et al. Angew. Chem. Int. Ed., 2021, 60, 7710-7718.
[4] N. Chen, H. H. Wang, Y. M. Lee*, et al. Nat. Commun., 2021, 12, 2367.
[5] N. Chen, Y. Jing, J. T. Fan*, Y. M. Lee*, et al. Angew. Chem. Int. Ed., 2021, 60, 19272-19280.
[6] C. Hu. N. Chen*, Y. M. Lee*, et al. J. Mater. Chem. A, 2022, DOI: 10.1039/D2TA00196A.
Biography
Nanjun Chen received a BS and Ph.D degree in Chemical Engineering and Technology from Beijing University of Chemical Technology working with Prof. Hong Zhu, following by a post-doctoral research position at Hanyang University under Prof. Young Moo Lee’s guideline from 2019. He joined Prof. Xile Hu’s group in École Polytechnique Fédérale de Lausanne (EPFL) and continued his second postdoc research from 2021 to develop next-generation PGM-free AEMFCs and AEMWEs. He has worked on developing high-performance anion exchange membranes and ionomers for cost-effective alkaline energy devices over nine years. He has been involved in several collaborations and has co-authored a total of 36 peer-reviewed journal articles (Energy Environ. Sci.; Nat. Commun.; Angew. Chem. Int. Ed.; Prog. Polym. Sci.; Trends in Chemistry; J. Mater. Chem. A. ACS Appl. Mater. Interfaces.; J. Membr. Sci.; J. Power Source), including 18 first-author and 5 co-corresponding-author articles. He has a co-inventor of 1 PCT patent application, 3 South Korean patent applications, and 3 Chinese patent applications.
Event details
Zoom webinar link: https://imperial-ac-uk.zoom.us/j/94871285008?pwd=VjJNdDl2YzdpMUt3TTV1T3hhRDRzUT09
Webinar ID: 948 7128 5008
Passcode: Mem@2022