Poly(Dibenzothiophene‐Terphenyl Piperidinium) for High‐Performance Anion Exchange Membrane Water Electrolysis

• Published in: Angewandte Chemie International Edition 2024-08, Vol.63 (34), p.e202405738-n/a
• Main Authors: Zheng, Wentao, He, Lanlan, Tang, Tang, Ren, Rong, Lee, Husileng, Ding, Guoheng, Wang, Linqin, Sun, Licheng
• Format: Article
• Language: English
• Subjects: Alkaline water; Anion exchange; Anion exchange membrane water electrolysis; Anion exchanging; Conductivity; Dibenzothiophene; Electrolysis; Green hydrogen; Highways; Hopping conduction; Hydrogen bond network; Hydrogen bonds; Membranes; OH− conducting highway; Sulfur
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.202405738

The anion exchange membrane water electrolysis is widely regarded as the next‐generation technology for producing green hydrogen. The OH− conductivity of the anion exchange membrane plays a key role in the practical implementation of this device. Here, we present a series of Z−S‐x membranes with dibenzothiophene groups. These membranes contain sulfur‐enhanced hydrogen bond networks that link surrounding surface site hopping regions, forming continuous OH− conducting highways. Z−S‐20 has a high through‐plane OH− conductivity of 182±28 mS cm−1 and ultralong stability of 2650 h in KOH solution at 80 °C. Based on rational design, we achieved a high PGM‐free alkaline water electrolysis performance of 7.12 A cm−2 at 2.0 V in a flow cell and demonstrated durability of 650 h at 2 A cm−2 at 40 °C with a cell voltage increase of 0.65 mV/h. With the introduction of dibenzothiophene into poly(aryl piperidinium) membrane, the sulfur‐enhanced hydrogen bond networks can efficiently transport the OH− ions through continuous OH− ions conducting highways, leading to significant improvement of anion exchange membrane water electrolysis.