Journal
ACS APPLIED ENERGY MATERIALS
Volume 6, Issue 19, Pages 9864-9874Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acsaem.3c01202
Keywords
anion-exchange membrane; membrane modification; Mannich reaction; multication; alkaline stability
Ask authors/readers for more resources
The main issues with anion exchange membranes (AEMs) are their low ionic conductivity and their inability to retain ion conductivity. This study presents the development of a series of multication AEMs to address these issues, with the most significant innovation being the synthesis of a multication AEM modified with cyclohexyl ammonium (QPE-MCy/OH-). The QPE-MCy-40/OH- membrane exhibits exceptional alkaline stability and ionic conductivity.
The main issues with anion exchange membranes (AEMs) are their low ionic conductivity and their inability to retain ion conductivity. To address these problems, we have developed a series of multication AEMs with varying ratios of dimethylamine, pyrrolidine, or methyl cyclohexylamine (20, 30, 40, 50, and 60%). The most significant innovation presented in this study is the synthesis of a multication AEM modified with cyclohexyl ammonium (QPE-MCy/OH-). This modification involves placing the nitrogen atom in the equatorial position of the cyclohexane ring to prevent 1,3-diaxial repulsion. As a result, there are no hydrogens at the proper angle for Hoffman's elimination. Consequently, the QPE-MCy-40/OH- membrane exhibits stability due to the inability of the quaternary ammonium salt group to nucleophilically attack the cyclohexane ring (due to the large size of the ring). The OH- conductivity of QPE-MCy-40/OH- reaches 103 mS cm(-1) at 80 degrees C in a 2 M NaOH solution. The alkaline chemical stability of the AEMs reveals that membranes containing cyclohexyl groups (QPE-MCy-40) exhibit exceptional alkaline stability with 95% retention of ionic conductivity in a 2 M NaOH solution at 80 degrees C after 480 h. When applied in a direct ethanol fuel cell (DEFC), QPE-MCy-40 membranes demonstrate superior single-cell performance, with a peak power density of 110 mW cm(-2) at 80 degrees C.
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