Nanochannel electrodes facilitating interfacial transport for PEM water electrolysis

• DOI: 10.1016/j.joule.2024.06.005
• Publication Date: 2024-06-25T14:46:08Z
• Authors: Jason K. Lee; Finn Babbe; Guanzhi Wang; Andrew W. Tricker; Rangachary Mukundan; Adam Z. Weber; Xiong Peng
• Keywords: Electrolysis of water; Ohmic contact; Water Transport

Proton-exchange membrane water electrolyzers (PEMWEs) are a promising technology for green hydrogen production; however, interfacial transport behaviors poorly understood, hindering device performance and longevity. Here, we first utilized finite-gap electrolyzer to demonstrate the possibility of proton transfer through in PEMWEs. The measured high-frequency resistances (HFRs) exhibit linear trend with increasing gap distance, where extrapolation shows lower value compared HFRs regular zero-gap electrolyzers, indicating that ohmic resistance could be further reduced. We introduce nanochannels facilitate mass transport, as evidenced by both liquid-fed vapor-fed electrolysis. Nanochannel electrodes achieve voltage reduction 190 mV at 9 A·cm−2 Ir-PTEs without nanochannels. Furthermore, nanochannel show negligible degradation 100,000 accelerated-stress tests over 2,000 h operation 1.8 decay rate 11.66 μV·h−1. These results provide new insights into localized dynamics PEMWEs highlight significance engineering electrochemical devices.