Journal
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Volume 116, Issue 20, Pages 9729-9734Publisher
NATL ACAD SCIENCES
DOI: 10.1073/pnas.1900988116
Keywords
alkaline anion exchange membrane; trans-cyclooctene; block and random copolymer; cross-linked polymer; transmission electron microscopy
Categories
Funding
- Center for Alkaline-based Energy Solutions, an Energy Frontier Research Center - US Department of Energy, Office of Science, Basic Energy Sciences Award [DE-SC0019445]
- NSF [CHE-1531632, DGE-1650441]
- NSF Materials Research Science and Engineering Centers [DMR-1719875]
Ask authors/readers for more resources
Alkaline anion exchange membranes (AAEMs) are an important component of alkaline exchange membrane fuel cells (AEMFCs), which facilitate the efficient conversion of fuels to electricity using nonplatinum electrode catalysts. However, low hydroxide conductivity and poor long-term alkaline stability of AAEMs are the major limitations for the widespread application of AEMFCs. In this paper, we report the synthesis of highly conductive and chemically stable AAEMs from the living polymerization of trans-cyclooctenes. A trans-cyclooctene-fused imidazolium monomer was designed and synthesized on gram scale. Using these highly ring-strained monomers, we produced a range of block and random copolymers. Surprisingly, AAEMs made from the random copolymer exhibited much higher conductivities than their block copolymer analogs. Investigation by transmission electron microscopy showed that the block copolymers had a disordered microphase segregation which likely impeded ion conduction. A cross-linked random copolymer demonstrated a high level of hydroxide conductivity (134 mS/cm at 80 degrees C). More importantly, the membranes exhibited excellent chemical stability due to the incorporation of highly alkaline-stable multisubstituted imidazolium cations. No chemical degradation was detected by H-1 NMR spectroscopy when the polymers were treated with 2 M KOH in CD3OH at 80 degrees C for 30 d.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available