1. Highly quaternized polystyrene ionomers for high performance anion exchange membrane water electrolysers
- Author
-
Yuehe Lin, Dongguo Li, Eun Joo Park, Cy Fujimoto, Yang Zhou, Ehren Baca, Barr Zulevi, Wenlei Zhu, Alexey Serov, Hoon T Chung, Yu Seung Kim, Hangyu Tian, and Qiurong Shi
- Subjects
Materials science ,Ion exchange ,Renewable Energy, Sustainability and the Environment ,Oxygen evolution ,Energy Engineering and Power Technology ,Proton exchange membrane fuel cell ,02 engineering and technology ,Alkaline anion exchange membrane ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrocatalyst ,01 natural sciences ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,Fuel Technology ,Membrane ,chemistry ,Chemical engineering ,Hydrogen fuel ,0210 nano-technology ,Ionomer - Abstract
Alkaline anion exchange membrane (AEM) electrolysers to produce hydrogen from water are still at an early stage of development, and their performance is far lower than that of systems based on proton exchange membranes. Here, we report an ammonium-enriched anion exchange ionomer that improves the performance of an AEM electrolyser to levels approaching that of state-of-the-art proton exchange membrane electrolysers. Using rotating-disk electrode experiments, we show that a high pH (>13) in the electrode binder is the critical factor for improving the activity of the hydrogen- and oxygen-evolution reactions in AEM electrolysers. Based on this observation, we prepared and tested several quaternized polystyrene electrode binders in an AEM electrolyser. Using the binder with the highest ionic concentration and a NiFe oxygen evolution catalyst, we demonstrated performance of 2.7 A cm−2 at 1.8 V without a corrosive circulating alkaline solution. The limited durability of the AEM electrolyser remains a challenge to be addressed in the future. Anion exchange membrane water electrolysers have potential cost advantages over proton exchange membrane electrolysers, but their performance has lagged behind. Here the authors investigate the cause of the poor performance of anion exchange membrane electrolysers and design ionomers that can overcome some of the challenges.
- Published
- 2020