Advanced Patterned Membranes for Efficient Alkaline Membrane Electrolyzers

Hu, Chuan; Lee, Young Jun; Ma, Yichang; Zhang, Xiaohua; Jung, Seung Won; Hwang, Hyewon; Cho, Hyeon Keun; Kim, Myeong-Geun; Yoo, Sung Jong; Zhang, Qiugen; Lee, Young Moo

doi:10.1021/acsenergylett.4c00207

Cited by 10 publications

(1 citation statement)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Likewise, the actual H 2 flow rate of the PTPA-based cell is 20.81 mL min –1 , and the Faradaic efficiency is 99.62% (Figure S28). It should be noted that, either in Faradaic efficiency or hydrogen purity, PCHTPA-based electrolyzer is slightly lower than that of PTPA counterpart, which is rational for the presence of micropores in PCHTPA membrane, but nevertheless, the over 98% Faradaic efficiency with the hydrogen purity of 99.9% are the competitive values in water electrolysis community. − …”

Section: Results and Discussionmentioning

confidence: 95%

Poly(spirofluorene)-Based Anion Exchange Membranes for Alkaline Electrochemical Energy Devices

Wang,

Zhang,

Wang

et al. 2024

Macromolecules

View full text Add to dashboard Cite

Anion exchange membranes (AEMs) with high conductivity and low hydrogen permeability guarantee efficient and reliable AEM fuel cells (AEMFCs) and water electrolyzers (AEMWEs). In this work, two monomeric spirofluorenes, spiro-[cyclopentane-1,9′-fluorene] (CPF) and spiro[cyclohexane-1,9′-fluorene] (CHF), were synthesized by a ring-closing reaction and further embedded into the poly(arylene alkylene) backbone to lower the ion transport resistance without compromising the gas barrier property of the AEM. The π−π stacking of the polymer backbone is weakened by the introduction of spirofluorene units, contributing to increased intermolecular spacing and improved microporous contents. On the other hand, despite the presence of spirocyclic units, an affordable low specific H 2 permeation of 28 pmol cm −1 s −1 was observed for the AEM. Moreover, an excellent hydroxide conductivity of 169 mS cm −1 at 80 °C was also recorded owing to the rapid ion transport caused by the microporosity. Benefiting from the good performance of the AEM, the engineered AEMFC based on PCHTPA exhibits a peak power density of 1.3 W cm −2 and an in situ durability of 330 h. Moreover, AEMWE shows a high current density of 3.2 A cm −2 at 2.0 V and excellent Faradaic efficiency of 98.4% with a hydrogen purity of 99.92%.

show abstract

Section: Results and Discussionmentioning

confidence: 95%

Poly(spirofluorene)-Based Anion Exchange Membranes for Alkaline Electrochemical Energy Devices

Wang,

Zhang,

Wang

et al. 2024

Macromolecules

View full text Add to dashboard Cite

show abstract

High‐Performance Anion Exchange Membrane Water Electrolyzers Enabled by Highly Gas Permeable and Dimensionally Stable Anion Exchange Ionomers

Liu,

Miyatake,

Tanabe

et al. 2024

Advanced Science

View full text Add to dashboard Cite

Designing suitable anion exchange ionomers is critical to improving the performance and in situ durability of anion exchange membrane water electrolyzers (AEMWEs) as one of the promising devices for producing green hydrogen. Herein, highly gas‐permeable and dimensionally stable anion exchange ionomers (QC6xBA and QC6xPA) are developed, in which bulky cyclohexyl (C6) groups are introduced into the polymer backbones. QC650BA‐2.1 containing 50 mol% C6 composition shows 16.6 times higher H2 permeability and 22.3 times higher O2 permeability than that of QC60BA‐2.1 without C6 groups. Through‐plane swelling of QC650BA‐2.1 decreases to 12.5% from 31.1% (QC60BA‐2.1) while OH− conductivity slightly decreases (64.9 and 56.2 mS cm−1 for QC60BA‐2.1 and QC650BA‐2.1, respectively, at 30 °C). The water electrolysis cell using the highly gas permeable QC650BA‐2.1 ionomer and Ni0.8Co0.2O in the anode catalyst layer achieves two times higher performance (2.0 A cm−2 at 1.69 V, IR‐included) than those of the previous cell using in‐house ionomer (QPAF‐4‐2.0) (1.0 A cm−2 at 1.69 V, IR‐included). During 1000 h operation at 1.0 A cm−2, the QC650BA‐2.1 cell exhibits nearly constant cell voltage with a decay rate of 1.1 µV h−1 after the initial increase of the cell voltage, proving the effectiveness of the highly gas permeable and dimensionally stable ionomer in AEMWEs.

show abstract

High‐Performance Pure Water‐Fed Anion Exchange Membrane Water Electrolysis with Patterned Membrane via Mechanical Stress and Hydration‐Mediated Patterning Technique

Lee,

Kim,

Shin

et al. 2024

Advanced Science

View full text Add to dashboard Cite

Despite rapid advancements in anion exchange membrane water electrolysis (AEMWE) technology, achieving pure water‐fed AEMWE remains critical for system simplification and cost reduction. Under pure water‐fed conditions, electrochemical reactions occur solely at active sites connected to ionic networks. This study introduces an eco‐friendly patterning technique leveraging membrane swelling properties by applying mechanical stress during dehydration under fixed constraints. The method increases active sites by creating additional hydroxide ion pathways at the membrane‐electrode interface, eliminating the need for additional ionomers in the electrode. This innovation facilitates ion conduction via locally shortened pathways. Membrane electrode assemblies (MEAs) with patterned commercial membranes demonstrated significantly improved performance and durability compared to MEAs with conventional catalyst‐coated substrates and flat membranes under pure water‐fed conditions. The universal applicability of this technique was confirmed using in‐house fabricated anion exchange membranes, achieving exceptional current densities of 13.7 A cm−2 at 2.0 V in 1.0 M potassium hydroxide (KOH) and 2.8 A cm−2 at 2.0 V in pure water at 60 °C. Furthermore, the scalability of the technique was demonstrated through successful fabrication and operation of large‐area cells. These findings highlight the potential of this patterning method to advance AEMWE technology, enabling practical applications under pure water‐fed conditions.

show abstract

Advanced Patterned Membranes for Efficient Alkaline Membrane Electrolyzers

Cited by 10 publications

References 45 publications

Poly(spirofluorene)-Based Anion Exchange Membranes for Alkaline Electrochemical Energy Devices

Poly(spirofluorene)-Based Anion Exchange Membranes for Alkaline Electrochemical Energy Devices

High‐Performance Anion Exchange Membrane Water Electrolyzers Enabled by Highly Gas Permeable and Dimensionally Stable Anion Exchange Ionomers

High‐Performance Pure Water‐Fed Anion Exchange Membrane Water Electrolysis with Patterned Membrane via Mechanical Stress and Hydration‐Mediated Patterning Technique

Contact Info

Product

Resources

About