A catalyst-coated diaphragm assembly to improve the performance and energy efficiency of alkaline water electrolysers

Zhuang Xu; Yanying Liu; Xiaobo Cheng; Yunshan Shang; Yongtao Wang; Jing Wang; Wenshi Li; Guangli He

doi:10.1038/s44172-025-00344-2

A catalyst-coated diaphragm assembly to improve the performance and energy efficiency of alkaline water electrolysers

Commun Eng. 2025 Jan 25;4(1):9. doi: 10.1038/s44172-025-00344-2.

Authors

Zhuang Xu¹, Yanying Liu¹, Xiaobo Cheng¹, Yunshan Shang¹, Yongtao Wang¹, Jing Wang¹, Wenshi Li¹, Guangli He²

Affiliations

¹ Hydrogen and Ammonium Energy R&D Center, National Institute of Clean-and-Low-Carbon Energy, Beijing, China.
² Hydrogen and Ammonium Energy R&D Center, National Institute of Clean-and-Low-Carbon Energy, Beijing, China. guangli.he@chnenergy.com.cn.

Abstract

Alkaline water electrolysers are ideal for gigawatt-scale hydrogen production due to the usage of non-precious metal and low-cost raw materials. However, their performances are modest with the separated electrode and diaphragm structure which can date back to more than 100 years ago. Here we report a catalyst-coated diaphragm assembly to improve the performance of alkaline water electrolysers. The transport resistance of OH^- ions is reduced and the electrochemical surface area of catalysts is enlarged by more than forty fold, representing more than 40% increase in hydrogen production rate or as much as 16% reduction in energy consumption. The electrolyser with our catalyst-coated diaphragm assembly delivers current densities as high as 1 A cm^-2 at 1.8 V or 2 A cm^-2 at 2 V and shows good stability after more than 1000 hours of operation. Therefore, the catalyst-coated diaphragm assembly route is promising for the development of high-performance and efficient alkaline water electrolysers.