Near-neutral pH water electrolysis driven by renewable electricity can reduce the costs of clean hydrogen generation, but its low efficiency and gas crossover in industrially relevant conditions remain a challenge. Here, it was shown that electrolyte engineering could suppress the crossover of dissolved gases such as O2 by regulating their diffusion flux. In addition, a hydrophilized mechanically stable glass sheet was found to block the permeation of gas bubbles, further enhancing the purity of evolved gas from water electrolysis. This sheet had a lower resistance than conventional diaphragms such as Zirfon due to its high porosity and small thickness. A saturated K-phosphate solution at pH 7.2 was used as an electrolyte together with the hydrophilized glass sheet as a gas-separator. This led to a near-neutral pH water electrolysis with 100 mA cm−2 at a total cell voltage of 1.56 V with 99.9 % purity of produced H2.
|Original language||English (US)|
|State||Published - Dec 14 2021|
Bibliographical noteKAUST Repository Item: Exported on 2022-05-25
Acknowledged KAUST grant number(s): OSR #4191
Acknowledgements: A part of this work was supported by Asahi Kasei Corporation, UTokyo-KAUST collaborative research OSR #4191 “Towards Sustainable Production of H2”, JSPS KAKENHI Grant Number 19K23569, and the Mohammed bin Salman Center for Future Science and Technology for Saudi-Japan Vision 2030 at The University of Tokyo (MbSC2030).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
ASJC Scopus subject areas
- Environmental Chemistry
- Materials Science(all)
- Chemical Engineering(all)