Journal
JOURNAL OF POWER SOURCES
Volume 490, Issue -, Pages -Publisher
ELSEVIER
DOI: 10.1016/j.jpowsour.2021.229544
Keywords
Anion exchange membrane; N-spirocyclic cation; Rod-coil grafts; Microphase-separated structure; High power density
Funding
- National Key Research and Development Program of China [2016YFB0101203]
- National Science Foundation of China [21776034, U1663223]
- Fundamental Research Funds for the Central Universities [DUT20LAB307]
- Education Department of the Liaoning Province of China [LT2015007]
- Changjiang Scholars Program [T2012049]
- Science Fund for Creative Research Groups of the National Natural Science Foundation of China [22021005]
Ask authors/readers for more resources
The study proposed a rod-coil grafts design to enhance microphase separation in N-spirocyclic anion exchange membranes, resulting in improved conductivity and toughness. By optimizing the n-octylamine hydrophobic coil graft length, the N-spirocyclic AEM showed high OH- conductivity and power density, placing it among the top level of cycloaliphatic AEMs reported in literature.
N-spirocyclic cations possess double-cyclic non-planar structure that exhibit the highest alkali stability among quaternary ammonium cations, however, the extremely rigidity usually causes fragile membranes and poor conductivity. In this work, a rod-coil grafts design is proposed for N-spirocyclic anion exchange membranes (AEMs), in which microphase separation of the hydrophilic N-spirocyclic rod grafts is significantly improved by the hydrophobic aggregation of the flexible alkyl coil grafts with polysulfone backbone. Molecular dynamic simulations indicate that the coil grafts contribute to microphase separation but fill in free volume to reduce water reservoir, therefore the rod-coil grafts design provides a way to evaluate the effects of microphase separation and free volume on conductivity. The increasing conductivity with the length of coil grafts suggests a greater contribution of good microphase separation to OH- conduction. With optimized n-octylamine hydrophobic coil graft length, the N-spirocyclic AEM exhibits toughness (elongation at break of about 28.7%) and high OH- conductivity (136.2 mS cm(-1) at 80 degrees C), resulting in high power density (850.1 mW cm(-2)), which is far greater than that assemble with other N-spirocyclic AEMs, and also bring N-spirocyclic AEMs into the top level of the cycloaliphatic AEMs reported in literatures.
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