%0 Journal Article
%A Pongsarun Satjaritanun
%A Maeve O'Brien
%A Devashish Kulkarni
%A Sirivatch Shimpalee
%A Cristopher Capuano
%A Katherine E Ayers
%A Nemanja Danilovic
%A Dilworth Y Parkinson
%A Iryna V Zenyuk
%B iScience
%D 2020
%G eng
%N 12
%P 101783
%R 10.1016/j.isci.2020.101783
%T Observation of Preferential Pathways for Oxygen Removal through Porous Transport Layers of Polymer Electrolyte Water Electrolyzers
%V 23
%8 11/2020
%! iScience
%X <p>Understanding the relationships between porous transport layer (PTL) morphology and oxygen removal is essential to improve the polymer electrolyte water electrolyzer (PEWE) performance. Operando X-ray computed tomography and machine learning were performed on a model electrolyzer at different water flow rates and current densities to determine how these operating conditions alter oxygen transport in the PTLs. We report a direct observation of oxygen taking preferential pathways through the PTL, regardless of the water flow rate or current density (1-4 A/cm2). Oxygen distribution in the PTL had a periodic behavior with period of 400 μm. A computational fluid dynamics model was used to predict oxygen distribution in the PTL showing periodic oxygen front. Observed oxygen distribution is due to low in-plane PTL tortuosity and high porosity enabling merging of oxygen bubbles in the middle of the PTL and also due to aerophobicity of the layer.</p>