Modifying Ionic Membranes with Carbon Dots Enables Direct Production of High-Purity Hydrogen through Water Electrolysis

Wang, Song; Zhang, Daliang; Ma, Xiaohua; Liu, Jiucong; Chen, Yanli; Zhao, Yunfeng; Han, Yu

Modifying Ionic Membranes with Carbon Dots Enables Direct Production of High-Purity Hydrogen through Water Electrolysis

Embargo End Date

2022-08-16

Type

Article

Authors

Wang, Song
Zhang, Daliang
Ma, Xiaohua

Liu, Jiucong
Chen, Yanli
Zhao, Yunfeng

Han, Yu

KAUST Department

Advanced Membranes and Porous Materials Research Center
Chemical Science Program
Nanostructured Functional Materials (NFM) laboratory
Physical Science and Engineering (PSE) Division

Online Publication Date

2021-08-16

Print Publication Date

2021-08-25

Date

2021-08-16

Submitted Date

2021-05-18

Abstract

Traditional electrolysis of water produces hydrogen with a purity of ∼98%. Using ion transport membranes to prevent the migration of oxygen (O2) from the anode to the cathode, the purity of H2 can be increased to ∼99.8%, but it still cannot fulfill the requirement for use in fuel cells (>99.97%). Here, we report that modifying a commercial ionic membrane (Nafion) with carbon dots (CDs) can further inhibit O2 permeation across the membrane, while effectively improving its ion transportability. The key to achieve these effects is the rational design and proper loading of the CDs, which narrows the pore size of the membrane from ∼4 nm to <2 nm and alters its surface functionality. Using the CDs-modified Nafion membrane in an H-type electrolysis cell, we demonstrate that H2 with a purity of up to 99.98%, which meets the standards of hydrogen fuel cells, can be directly produced without any additional purification process. Our study provides a new route for the low-cost electrolysis of water to produce high-purity hydrogen.

Citation

Wang, S., Zhang, D., Ma, X., Liu, J., Chen, Y., Zhao, Y., & Han, Y. (2021). Modifying Ionic Membranes with Carbon Dots Enables Direct Production of High-Purity Hydrogen through Water Electrolysis. ACS Applied Materials & Interfaces. doi:10.1021/acsami.1c09214

Acknowledgements

This work was supported by the open fund of the key laboratory of advanced functional polymer materials, the ministry of education (KLFPM202001) and the National Natural Science Foundation of China (grant no: 22078245).