High CO and sulfur tolerant proton exchange membrane fuel cell anodes enabled by "work along both lines" mechanism of 2,6-dihydroxymethyl pyridine molecule blocking layer

Dongqing Zhang; Wenqi Liu; Ke Ye; Xiaojin Li

doi:10.1016/j.jcis.2023.09.076

High CO and sulfur tolerant proton exchange membrane fuel cell anodes enabled by "work along both lines" mechanism of 2,6-dihydroxymethyl pyridine molecule blocking layer

J Colloid Interface Sci. 2024 Jan;653(Pt A):413-422. doi: 10.1016/j.jcis.2023.09.076. Epub 2023 Sep 12.

Authors

Dongqing Zhang¹, Wenqi Liu², Ke Ye², Xiaojin Li³

Affiliations

¹ Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, Shandong, China; University of Chinese Academy of Sciences, Beijing 100049, China.
² Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, Shandong, China.
³ Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao 266101, Shandong, China; University of Chinese Academy of Sciences, Beijing 100049, China; Shandong Energy Institute, Qingdao 266101, Shandong, China. Electronic address: lixj@qibebt.ac.cn.

PMID: 37722170
DOI: 10.1016/j.jcis.2023.09.076

Abstract

Proton exchange membrane fuel cells (PEMFCs) are hindered by their poor tolerance to CO and H₂S poisoning. Herein, we report an effective method, via engineering 2,6-dihydroxymethyl pyridine (DhmPy) molecule blocking layers on Pt surface, aiming to save the poisoning issue for PEMFC anode reaction. The PEMFCs assembled by this catalyst produce a power density of 1.18 W cm^-2 @ 2.0 A cm^-2 and 1.32 W cm^-2 @ 2.0 A cm^-2, far exceeding commercial Pt/C after H₂/10 ppm CO poisoning and H₂/5 ppm H₂S poisoning tests, respectively. Density functional theory (DFT) indicates that a coronal molecule layer with a steric confinement height (1.82 Å), constructed by DhmPy, emerges more intensive adsorption energy compared to 2,6-pyridinedicarboxamide (DcaPy) and 2,6-diacetylpyridine (DAcPy), thereby more effectively inhibits the adsorption of large-sized CO and H₂S on Pt surface without affecting H₂ traverse. This "work along both lines" mechanism with the resistance of both CO and H₂S provides a new and promising design thought for high CO and sulfur tolerant PEMFC anodes.

Keywords: CO tolerance; Density functional theory; Molecule blocking layer; Proton exchange membrane fuel cell anode; Sulfur tolerance.